update

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

.buildkite/pipeline.yml

@@ -22,7 +22,7 @@ steps:
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
-                command: "timeout 15m .buildkite/scripts/pr_test.sh"
+                command: "timeout 20m .buildkite/scripts/pr_test.sh"
                 label: "Encoder Tests"
                 env:
                   - TEST_TYPE=encoder
@@ -35,7 +35,7 @@ steps:
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
-                command: "timeout 15m .buildkite/scripts/pr_test.sh"
+                command: "timeout 20m .buildkite/scripts/pr_test.sh"
                 label: "VAE Tests"
                 env:
                   - TEST_TYPE=vae
@@ -61,7 +61,7 @@ steps:
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
-                command: "timeout 45m .buildkite/scripts/pr_test.sh"
+                command: "timeout 60m .buildkite/scripts/pr_test.sh"
                 label: "SSIM Tests"
                 env:
                   - TEST_TYPE=ssim
@@ -76,7 +76,7 @@ steps:
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
-                command: "timeout 15m .buildkite/scripts/pr_test.sh"
+                command: "timeout 20m .buildkite/scripts/pr_test.sh"
                 label: "LoRA Inference Tests"
                 env:
                   - TEST_TYPE=inference_lora
@@ -93,6 +93,29 @@ steps:
                   - TEST_TYPE=training
                 agents:
                   queue: "default"
+            - path:
+                - "fastvideo/training/*distillation_pipeline.py"
+                - "pyproject.toml"
+                - "docker/Dockerfile.python3.12"
+              config:
+                command: "timeout 15m .buildkite/scripts/pr_test.sh"
+                label: "Distillation DMDTests"
+                env:
+                  - TEST_TYPE=distillation_dmd
+                agents:
+                  queue: "default"
+            - path:
+                - "fastvideo/training/*self_forcing_distillation_pipeline.py"
+                - "fastvideo/tests/training/self-forcing/**"
+                - "pyproject.toml"
+                - "docker/Dockerfile.python3.12"
+              config:
+                command: "timeout 15m .buildkite/scripts/pr_test.sh"
+                label: "Self-Forcing Tests"
+                env:
+                  - TEST_TYPE=self_forcing
+                agents:
+                  queue: "default"
             - path:
                 - "fastvideo/**"
                 - "pyproject.toml"
@@ -106,11 +129,7 @@ steps:
                   queue: "default"
             - path:
                 - "fastvideo/**"
-                - "csrc/attn/vsa/**"
-                - "csrc/attn/tk/**"
-                - "csrc/attn/setup_vsa.py"
-                - "csrc/attn/config_vsa.py"
-                - "csrc/attn/vsa.cpp"
+                - "fastvideo-kernel/**"
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
@@ -122,10 +141,7 @@ steps:
                   queue: "default"
             - path:
                 - "fastvideo/**"
-                - "csrc/attn/st_attn/**"
-                - "csrc/attn/setup_sta.py"
-                - "csrc/attn/config_sta.py"
-                - "csrc/attn/st_attn.cpp"
+                - "fastvideo-kernel/**"
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
@@ -136,31 +152,45 @@ steps:
                 agents:
                   queue: "default"
             - path:
-                - "csrc/attn/st_attn/**"
-                - "csrc/attn/setup_sta.py"
-                - "csrc/attn/config_sta.py"
-                - "csrc/attn/st_attn.cpp"
+                - "fastvideo-kernel/**"
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
                 command: "timeout 15m .buildkite/scripts/pr_test.sh"
-                label: "Precision Tests STA"
+                label: "Kernel Tests"
                 env:
-                  - TEST_TYPE=precision_sta
+                  - TEST_TYPE=kernel_tests
+            - path:
+                - "fastvideo-kernel/**"
+                - "fastvideo/attention/backends/vmoba.py"
+                - "pyproject.toml"
+                - "docker/Dockerfile.python3.12"
+              config:
+                command: "timeout 15m .buildkite/scripts/pr_test.sh"
+                label: "Inference Tests VMoBA"
+                env:  
+                  - TEST_TYPE=inference_vmoba
                 agents:
                   queue: "default"
             - path:
-                - "csrc/attn/vsa/**"
-                - "csrc/attn/tk/**"
-                - "csrc/attn/setup_vsa.py"
-                - "csrc/attn/config_vsa.py"
-                - "csrc/attn/vsa.cpp"
+                - "fastvideo/**"
                 - "pyproject.toml"
                 - "docker/Dockerfile.python3.12"
               config:
                 command: "timeout 15m .buildkite/scripts/pr_test.sh"
-                label: "Precision Tests VSA"
+                label: "Unit Tests"
                 env:
-                  - TEST_TYPE=precision_vsa
+                  - TEST_TYPE=unit_test
                 agents:
                   queue: "default"
+            # - path:
+            #     - "scripts/lora_extraction/**"
+            #     - "pyproject.toml"
+            #     - "docker/Dockerfile.python3.12"
+            #   config:
+            #     command: "timeout 90m .buildkite/scripts/pr_test.sh"
+            #     label: "LoRA Extraction Tests"
+            #     env:
+            #       - TEST_TYPE=lora_extraction
+            #     agents:
+            #       queue: "default"

.buildkite/scripts/pr_test.sh

@@ -31,9 +31,9 @@ log "Setting up Modal authentication from Buildkite secrets..."
 MODAL_TOKEN_ID=$(buildkite-agent secret get modal_token_id)
 MODAL_TOKEN_SECRET=$(buildkite-agent secret get modal_token_secret)
 
+# Retrieve other secrets
 WANDB_API_KEY=$(buildkite-agent secret get wandb_api_key)
-
-WANDB_API_KEY=$(buildkite-agent secret get wandb_api_key)
+HF_API_KEY=$(buildkite-agent secret get hf_api_key)
 
 if [ -n "$MODAL_TOKEN_ID" ] && [ -n "$MODAL_TOKEN_SECRET" ]; then
     log "Retrieved Modal credentials from Buildkite secrets"
@@ -63,19 +63,19 @@ MODAL_ENV="BUILDKITE_REPO=$BUILDKITE_REPO BUILDKITE_COMMIT=$BUILDKITE_COMMIT BUI
 case "$TEST_TYPE" in
     "encoder")
         log "Running encoder tests..."
-        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_encoder_tests"
+        MODAL_COMMAND="$MODAL_ENV HF_API_KEY=$HF_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_encoder_tests"
         ;;
     "vae")
         log "Running VAE tests..."
-        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_vae_tests"
+        MODAL_COMMAND="$MODAL_ENV HF_API_KEY=$HF_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_vae_tests"
         ;;
     "transformer")
         log "Running transformer tests..."
-        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_transformer_tests"
+        MODAL_COMMAND="$MODAL_ENV HF_API_KEY=$HF_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_transformer_tests"
         ;;
     "ssim")
         log "Running SSIM tests..."
-        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_ssim_tests"
+        MODAL_COMMAND="$MODAL_ENV HF_API_KEY=$HF_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_ssim_tests"
         ;;
     "training")
         log "Running training tests..."
@@ -93,18 +93,35 @@ case "$TEST_TYPE" in
         log "Running inference STA tests..."
         MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_inference_tests_STA"
         ;;
-    "precision_sta")
-        log "Running precision STA tests..."
-        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_precision_tests_STA"
-        ;;
-    "precision_vsa")
-        log "Running precision VSA tests..."
-        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_precision_tests_VSA"
+    "kernel_tests")
+        log "Running kernel tests..."
+        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_kernel_tests"
         ;;
     "inference_lora")
         log "Running LoRA tests..."
         MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_inference_lora_tests"
         ;;
+    "distillation_dmd")
+        log "Running distillation DMD tests..."
+        MODAL_COMMAND="$MODAL_ENV WANDB_API_KEY=$WANDB_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_distill_dmd_tests"
+        ;;
+        # run_inference_tests_vmoba
+    "self_forcing")
+        log "Running self-forcing tests..."
+        MODAL_COMMAND="$MODAL_ENV WANDB_API_KEY=$WANDB_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_self_forcing_tests"
+        ;;
+    "inference_vmoba")
+        log "Running V-MoBA inference tests..."
+        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_inference_tests_vmoba"
+        ;;
+    "unit_test")
+        log "Running unit tests..."
+        MODAL_COMMAND="$MODAL_ENV python3 -m modal run $MODAL_TEST_FILE::run_unit_test"
+        ;;
+    "lora_extraction")
+        log "Running LoRA extraction tests..."
+        MODAL_COMMAND="$MODAL_ENV HF_API_KEY=$HF_API_KEY python3 -m modal run $MODAL_TEST_FILE::run_lora_extraction_tests"
+        ;;
     *)
         log "Error: Unknown test type: $TEST_TYPE"
         exit 1

.github/workflows/build-image.yml

@@ -18,6 +18,12 @@ on:
         required: false
         default: false
         type: boolean
+      python_3_12_cuda_12_9:
+        description: 'Build Python 3.12 image Cuda 12.9'
+        required: false
+        default: false
+        type: boolean
+
 
 permissions:
   contents: read
@@ -49,4 +55,13 @@ jobs:
       python_version: '3.12'
       dockerfile_path: docker/Dockerfile.python3.12
       tag_suffix: py3.12
+    secrets: inherit
+
+  build-python-3-12-cuda-12-9:
+    if: ${{ github.event.inputs.python_3_12_cuda_12_9 == 'true' }}
+    uses: ./.github/workflows/build-image-template.yml
+    with:
+      python_version: '3.12'
+      dockerfile_path: docker/Dockerfile.python3.12.cuda12.9.1
+      tag_suffix: py3.12-cuda12.9.1
     secrets: inherit

.github/workflows/docs.yml

@@ -1,82 +1,65 @@
-# Sample workflow for building and deploying a Hugo site to GitHub Pages
-name: Deploy FastVideo Docs to Pages
+name: Deploy Documentation
 
 on:
-  # Runs on pushes targeting the default branch
   push:
-    branches:
-      - main
+    branches: [ main ]
     paths:
-      - "docs/**/*.md"
-      - "fastvideo/examples/**/*.py"
+      - 'docs/**'
+      - 'mkdocs.yml'
+      - 'requirements-mkdocs.txt'
+      - '.github/workflows/docs.yml'
   pull_request:
-    branches: 
-      - main
-    types: [opened, ready_for_review, synchronize, reopened]
+    branches: [ main ]
     paths:
-      - "docs/**/*.md"
-      - "fastvideo/examples/**/*.py"
+      - 'docs/**'
+      - 'mkdocs.yml'
+      - 'requirements-mkdocs.txt'
+      - '.github/workflows/docs.yml'
 
-  # Allows you to run this workflow manually from the Actions tab
-  workflow_dispatch:
-
-# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages
 permissions:
   contents: read
   pages: write
   id-token: write
 
-# Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
-# However, do NOT cancel in-progress runs as we want to allow these production deployments to complete.
 concurrency:
   group: "pages"
   cancel-in-progress: false
 
-# Default to bash
-defaults:
-  run:
-    shell: bash
-
 jobs:
-  pre-commit:
-    uses: ./.github/workflows/pre-commit.yml
-
-  # Build job
   build:
     runs-on: ubuntu-latest
-    needs: pre-commit
     steps:
       - name: Checkout
         uses: actions/checkout@v4
-      - name: Setup Pages
-        id: pages
-        uses: actions/configure-pages@v5
-      - name: Set up Python
+
+      - name: Setup Python
         uses: actions/setup-python@v5
         with:
-          python-version: "3.10"
+          python-version: '3.12'
+
       - name: Install dependencies
         run: |
-          cd docs
-          pip install -r requirements-docs.txt
-      - name: Build docs
-        run: |
-          cd docs
-          make clean
-          make html
+          python -m pip install --upgrade pip
+          pip install -r requirements-mkdocs.txt
+
+      - name: Setup Pages
+        uses: actions/configure-pages@v4
+
+      - name: Build documentation
+        run: mkdocs build
+
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v3
         with:
-          path: ./docs/build/html
+          path: ./site
 
-  # Deployment job
   deploy:
     environment:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
-    if: ${{ github.event_name == 'push' }}
     runs-on: ubuntu-latest
     needs: build
+    if: github.ref == 'refs/heads/main'
     steps:
       - name: Deploy to GitHub Pages
         id: deployment

.github/workflows/fastvideo-kernel-publish.yml

@@ -0,0 +1,207 @@
+name: Publish FastVideo Kernel to PyPI on Version Change
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "fastvideo-kernel/pyproject.toml"
+  workflow_dispatch:
+
+jobs:
+  check-version-change:
+    runs-on: ubuntu-latest
+    outputs:
+      version-changed: ${{ steps.check-version.outputs.changed }}
+      new-version: ${{ steps.check-version.outputs.new-version }}
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: Check if version changed
+        id: check-version
+        run: |
+          cd fastvideo-kernel
+          # Get current commit's version from pyproject.toml
+          # Use ^ to match start of line to avoid matching minimum-version
+          NEW_VERSION=$(grep -oP '^version\s*=\s*"\K[^"]+' pyproject.toml)
+          echo "New version: $NEW_VERSION"
+          
+          # Get previous version from git history
+          # Note: git show expects path relative to repo root
+          OLD_VERSION=$(git show HEAD~1:fastvideo-kernel/pyproject.toml | grep -oP '^version\s*=\s*"\K[^"]+' || echo "0.0.0")
+          echo "Old version: $OLD_VERSION"
+          
+          if [ "$NEW_VERSION" != "$OLD_VERSION" ]; then
+            echo "Version changed from $OLD_VERSION to $NEW_VERSION"
+            echo "changed=true" >> $GITHUB_OUTPUT
+            echo "new-version=$NEW_VERSION" >> $GITHUB_OUTPUT
+          else
+            echo "Version did not change"
+            echo "changed=false" >> $GITHUB_OUTPUT
+          fi
+
+  build_wheels:
+    name: Build Wheel
+    needs: check-version-change
+    if: ${{ needs.check-version-change.outputs.version-changed == 'true' || github.event_name == 'workflow_dispatch' }}
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+          os: [ubuntu-22.04]
+          python-version: ['3.10', '3.11', '3.12']
+          torch-cuda:
+            # - torch-version: '2.5.1'
+            #   cuda-version: '12.4.1'
+            #   torch-cuda-short: 'cu124'
+            # - torch-version: '2.6.0'
+            #   cuda-version: '12.6.3'
+            #   torch-cuda-short: 'cu126'
+            # - torch-version: '2.7.1'
+            #   cuda-version: '12.8.0'
+            #   torch-cuda-short: 'cu128'
+            - torch-version: '2.9.1'
+              cuda-version: '12.8.0'
+              torch-cuda-short: 'cu128'
+
+    steps:
+      - name: Free up disk space
+        run: |
+          echo "Initial disk space:"
+          df -h
+          
+          # Remove large directories
+          sudo rm -rf /usr/share/dotnet
+          sudo rm -rf /usr/local/lib/android
+          sudo rm -rf /opt/ghc
+          sudo rm -rf /usr/local/share/boost
+          sudo rm -rf /usr/share/swift
+          sudo rm -rf /usr/local/lib/node_modules
+          sudo rm -rf /usr/local/share/powershell
+          sudo rm -rf /usr/share/rust
+          sudo rm -rf /usr/local/.ghcup
+          
+          # Remove cached files
+          sudo rm -rf /var/lib/apt/lists/*
+          sudo rm -rf /var/cache/apt/archives/*
+          
+          echo "Disk space after cleanup:"
+          df -h
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install CUDA ${{ matrix.torch-cuda.cuda-version }}
+        uses: Jimver/cuda-toolkit@v0.2.21
+        id: cuda-toolkit
+        with:
+          cuda: ${{ matrix.torch-cuda.cuda-version }}
+          linux-local-args: '["--toolkit"]'
+          method: 'network'
+
+      - name: Install dependencies (GCC, Clang, CUDA Paths, Git)
+        run: |
+          sudo apt update
+          sudo apt install -y git patchelf gcc-11 g++-11 clang-11
+          sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+
+          # Allow Git to Access Safe Directory
+          git config --global --add safe.directory /__w/FastVideo/FastVideo
+
+          # Set CUDA environment variables
+          export CUDA_HOME=/usr/local/cuda-${{ matrix.torch-cuda.cuda-version }}
+          export PATH=${CUDA_HOME}/bin:${PATH}
+          export LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
+          
+          # Verify installation
+          gcc --version
+          g++ --version
+          clang-11 --version
+          nvcc --version
+
+      - name: Install PyTorch ${{ matrix.torch-cuda.torch-version }}+cu${{ matrix.torch-cuda.cuda-version }}
+        run: |
+          pip install --upgrade pip
+          pip install typing-extensions==4.12.2
+          pip install --no-cache-dir torch==${{ matrix.torch-cuda.torch-version }} --index-url https://download.pytorch.org/whl/${{matrix.torch-cuda.torch-cuda-short}}
+          nvcc --version
+          python --version
+          python -c "import torch; print('PyTorch:', torch.__version__)"
+          python -c "import torch; print('CUDA:', torch.version.cuda)"
+          python -c "from torch.utils import cpp_extension; print (cpp_extension.CUDA_HOME)"
+
+      - name: Build wheel
+        run: |
+          export PYTHONPATH=$GITHUB_WORKSPACE:$PYTHONPATH
+          
+          pip install setuptools ninja packaging wheel triton scikit-build-core cmake build
+          
+          cd fastvideo-kernel
+          git submodule update --init --recursive  # Ensure ThunderKittens submodule is initialized
+          # Release builds are produced on GPU-less runners, so force-enable TK and target Hopper.
+          export TORCH_CUDA_ARCH_LIST="9.0a"
+          export CMAKE_ARGS="${CMAKE_ARGS:-} -DFASTVIDEO_KERNEL_BUILD_TK=ON -DCMAKE_CUDA_ARCHITECTURES=90a"
+          
+          # Build standard wheel (no local version suffix) for PyPI
+          python -m build --wheel --outdir dist
+          
+          # Fix the wheel to be manylinux compliant
+          pip install auditwheel
+          # Target manylinux_2_35 (Ubuntu 22.04 native)
+          auditwheel repair dist/*.whl --plat manylinux_2_35_x86_64 -w fixed_dist
+          # Move fixed wheels back to dist for upload consistency
+          rm dist/*.whl
+          mv fixed_dist/*.whl dist/
+
+      - name: Upload wheel artifact
+        # Only upload if it's the "main" CUDA version we want on PyPI
+        # We upload all to artifacts for inspection/GH releases, but give them distinct artifact names
+        uses: actions/upload-artifact@v4
+        with:
+          name: fastvideo_kernel-py${{ matrix.python-version }}-${{ matrix.torch-cuda.torch-cuda-short }}-torch${{ matrix.torch-cuda.torch-version }}
+          path: fastvideo-kernel/dist/*.whl
+          retention-days: 90
+
+  publish_package:
+    name: Publish package
+    needs: [build_wheels, check-version-change]
+    if: ${{ needs.check-version-change.outputs.version-changed == 'true' || github.event_name == 'workflow_dispatch' }}
+    runs-on: ubuntu-22.04
+    permissions:
+      id-token: write  # Needed for OIDC Trusted Publishing
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+
+      - name: Download PyPI wheels
+        uses: actions/download-artifact@v4
+        with:
+          path: fastvideo-kernel/dist/
+          pattern: 'fastvideo_kernel-py*'
+          merge-multiple: true
+
+      - name: Build source distribution
+        run: |
+          pip install build scikit-build-core cmake ninja
+          
+          cd fastvideo-kernel
+          # We don't need full CUDA/Torch to just package the source (sdist)
+          python -m build --sdist --outdir dist
+
+      - name: Publish release distributions to PyPI
+        uses: pypa/gh-action-pypi-publish@release/v1
+        with:
+          packages-dir: fastvideo-kernel/dist/

.github/workflows/pr-test.yml

@@ -62,8 +62,8 @@ on:
         required: false
         default: false
         type: boolean
-      run_nightly_test:
-        description: "Run nightly-test"
+      run_unit_test:
+        description: "Run unit-test"
         required: false
         default: false
         type: boolean
@@ -93,6 +93,7 @@ jobs:
       inference-test-STA: ${{ steps.filter.outputs.inference-test-STA }}
       precision-test-STA: ${{ steps.filter.outputs.precision-test-STA }}
       precision-test-VSA: ${{ steps.filter.outputs.precision-test-VSA }}
+      unit-test: ${{ steps.filter.outputs.unit-test }}
     steps:
       - uses: actions/checkout@v4
       - uses: dorny/paths-filter@v3
@@ -102,18 +103,21 @@ jobs:
             # Define reusable path patterns
             common-paths: &common-paths
               - 'pyproject.toml'
+              - 'docker/Dockerfile.python3.10'
+              - 'docker/Dockerfile.python3.11'
               - 'docker/Dockerfile.python3.12'
             sta-kernel-paths: &sta-kernel-paths
-              - 'csrc/attn/st_attn/**'
-              - 'csrc/attn/setup_sta.py'
-              - 'csrc/attn/config_sta.py'
-              - 'csrc/attn/st_attn.cpp'
+              - 'csrc/attn/sliding_tile_attn/**'
+              - 'csrc/attn/sliding_tile_attn/tk/**'
+              - 'csrc/attn/sliding_tile_attn/setup.py'
+              - 'csrc/attn/sliding_tile_attn/config_sta.py'
+              - 'csrc/attn/sliding_tile_attn/st_attn.cpp'
             vsa-kernel-paths: &vsa-kernel-paths
-              - 'csrc/attn/vsa/**'
-              - 'csrc/attn/tk/**'
-              - 'csrc/attn/setup_vsa.py'
-              - 'csrc/attn/config_vsa.py'
-              - 'csrc/attn/vsa.cpp'
+              - 'csrc/attn/video_sparse_attn/**'
+              - 'csrc/attn/video_sparse_attn/tk/**'
+              - 'csrc/attn/video_sparse_attn/setup.py'
+              - 'csrc/attn/video_sparse_attn/config_vsa.py'
+              - 'csrc/attn/video_sparse_attn/vsa.cpp'
             vsa-paths: &vsa-paths
               - 'fastvideo/**'
               - *common-paths
@@ -154,6 +158,9 @@ jobs:
             precision-test-VSA:
               - *common-paths
               - *vsa-kernel-paths
+            unit-test:
+              - 'fastvideo/**'
+              - *common-paths
 
   encoder-test:
     needs: change-filter
@@ -234,7 +241,7 @@ jobs:
     secrets:
       RUNPOD_API_KEY: ${{ secrets.RUNPOD_API_KEY }}
       RUNPOD_PRIVATE_KEY: ${{ secrets.RUNPOD_PRIVATE_KEY }}
-  
+
   training-test:
     needs: change-filter
     if: >-
@@ -326,29 +333,48 @@ jobs:
       volume_size: 100
       disk_size: 100
       image: "ghcr.io/${{ github.repository }}/fastvideo-dev:py3.12-latest"
-      test_command: "uv pip install -e .[test] && python csrc/attn/tests/test_block_sparse.py"
+      test_command: "uv pip install -e .[test] && python csrc/attn/tests/test_vsa.py"
       timeout_minutes: 30
     secrets:
       RUNPOD_API_KEY: ${{ secrets.RUNPOD_API_KEY }}
       RUNPOD_PRIVATE_KEY: ${{ secrets.RUNPOD_PRIVATE_KEY }}
 
-  nightly-test:
+  unit-test:
+    needs: change-filter
     if: >-
-      (github.event_name == 'workflow_dispatch' && github.event.inputs.run_nightly_test == 'true')
+      (github.event_name != 'workflow_dispatch' && needs.change-filter.outputs.unit-test == 'true') || 
+      (github.event_name == 'workflow_dispatch' && github.event.inputs.run_unit_test == 'true')
     uses: ./.github/workflows/runpod-test.yml
     with:
-      job_id: "nightly-test"
-      gpu_type: "NVIDIA A40"
-      gpu_count: 4
+      job_id: "unit-test"
+      gpu_type: "NVIDIA L40S"
+      gpu_count: 1
       volume_size: 100
       disk_size: 100
       image: "ghcr.io/${{ github.repository }}/fastvideo-dev:py3.12-latest"
-      test_command: "wandb login $WANDB_API_KEY && uv pip install -e .[test] && pytest ./fastvideo/tests/nightly/test_e2e_overfit_single_sample.py -vs"
+      test_command: "uv pip install -e .[test] && pytest ./fastvideo/dataset/ -vs && pytest ./fastvideo/workflow/ -vs && pytest ./fastvideo/entrypoints/ -vs"
       timeout_minutes: 30
     secrets:
       RUNPOD_API_KEY: ${{ secrets.RUNPOD_API_KEY }}
       RUNPOD_PRIVATE_KEY: ${{ secrets.RUNPOD_PRIVATE_KEY }}
-      WANDB_API_KEY: ${{ secrets.WANDB_API_KEY }}
+
+  # nightly-test:
+  #   if: >-
+  #     (github.event_name == 'workflow_dispatch' && github.event.inputs.run_nightly_test == 'true')
+  #   uses: ./.github/workflows/runpod-test.yml
+  #   with:
+  #     job_id: "nightly-test"
+  #     gpu_type: "NVIDIA A40"
+  #     gpu_count: 4
+  #     volume_size: 100
+  #     disk_size: 100
+  #     image: "ghcr.io/${{ github.repository }}/fastvideo-dev:py3.12-latest"
+  #     test_command: "wandb login $WANDB_API_KEY && uv pip install -e .[test] && pytest ./fastvideo/tests/nightly/test_e2e_overfit_single_sample.py -vs"
+  #     timeout_minutes: 30
+  #   secrets:
+  #     RUNPOD_API_KEY: ${{ secrets.RUNPOD_API_KEY }}
+  #     RUNPOD_PRIVATE_KEY: ${{ secrets.RUNPOD_PRIVATE_KEY }}
+  #     WANDB_API_KEY: ${{ secrets.WANDB_API_KEY }}
 
   runpod-cleanup:
     # Add other jobs to this list as you create them
@@ -372,4 +398,4 @@ jobs:
           JOB_IDS: '["encoder-test", "vae-test", "transformer-test", "ssim-test-py3.10", "ssim-test-py3.11", "ssim-test-py3.12", "training-test", "training-test-VSA", "inference-test-STA", "precision-test-STA", "precision-test-VSA"]'
           RUNPOD_API_KEY: ${{ secrets.RUNPOD_API_KEY }}
           GITHUB_RUN_ID: ${{ github.run_id }}
-        run: python .github/scripts/runpod_cleanup.py
+        run: python .github/scripts/runpod_cleanup.py

.github/workflows/sta-publish.yml

@@ -5,7 +5,7 @@ on:
     branches:
       - main
     paths:
-      - "csrc/attn/setup_sta.py"
+      - "csrc/attn/sliding_tile_attn/setup.py"
   workflow_dispatch:
 
 jobs:
@@ -23,13 +23,13 @@ jobs:
       - name: Check if version changed
         id: check-version
         run: |
-          cd csrc/attn
+          cd csrc/attn/sliding_tile_attn
           # Get current commit's version
-          NEW_VERSION=$(grep -oP 'VERSION\s*=\s*"\K[^"]+' setup_sta.py)
+          NEW_VERSION=$(grep -oP 'VERSION\s*=\s*"\K[^"]+' setup.py)
           echo "New version: $NEW_VERSION"
           
           # Get previous version from git history
-          OLD_VERSION=$(git show HEAD~1:./setup_sta.py | grep -oP 'VERSION\s*=\s*"\K[^"]+' || echo "0.0.0")
+          OLD_VERSION=$(git show HEAD~1:./setup.py | grep -oP 'VERSION\s*=\s*"\K[^"]+' || echo "0.0.0")
           echo "Old version: $OLD_VERSION"
           
           if [ "$NEW_VERSION" != "$OLD_VERSION" ]; then
@@ -144,13 +144,13 @@ jobs:
           pip install setuptools
           pip install ninja packaging wheel
 
-          cd csrc/attn  # Move into the correct folder
+          cd csrc/attn/sliding_tile_attn  # Move into the correct folder
           git submodule update --init --recursive # Ensure ThunderKittens submodule is initialized
-          python setup_sta.py bdist_wheel --dist-dir=dist
+          python setup.py bdist_wheel --dist-dir=dist
 
       - name: Rename wheel file
         run: |
-          cd csrc/attn
+          cd csrc/attn/sliding_tile_attn
 
           CUDA_SHORT_VERSION=$(echo ${{ matrix.cuda-version }} | cut -d. -f1,2 | sed 's/\.//g')
           TORCH_SHORT_VERSION=$(echo ${{ matrix.torch-version }} | cut -d. -f1,2)
@@ -165,7 +165,7 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: ${{ env.wheel_name }}
-          path: csrc/attn/dist/*.whl
+          path: csrc/attn/sliding_tile_attn/dist/*.whl
           retention-days: 90
 
   publish_package:
@@ -239,11 +239,11 @@ jobs:
           pip install setuptools
           pip install ninja packaging wheel
 
-          cd csrc/attn  # Move into the correct folder
+          cd csrc/attn/sliding_tile_attn  # Move into the correct folder
           git submodule update --init --recursive # Ensure ThunderKittens submodule is initialized
-          python setup_sta.py sdist --dist-dir=dist
+          python setup.py sdist --dist-dir=dist
 
       - name: Publish release distributions to PyPI
         uses: pypa/gh-action-pypi-publish@release/v1
         with:
-          packages-dir: csrc/attn/dist/
+          packages-dir: csrc/attn/sliding_tile_attn/dist/

.github/workflows/vsa-publish.yml

@@ -0,0 +1,257 @@
+name: Publish Video Sparse Attention Kernel to PyPI on Version Change
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "csrc/attn/video_sparse_attn/setup.py"
+  workflow_dispatch:
+
+jobs:
+  check-version-change:
+    runs-on: ubuntu-latest
+    outputs:
+      version-changed: ${{ steps.check-version.outputs.changed }}
+      new-version: ${{ steps.check-version.outputs.new-version }}
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: Check if version changed
+        id: check-version
+        run: |
+          cd csrc/attn/video_sparse_attn
+          # Get current commit's version
+          NEW_VERSION=$(grep -oP 'VERSION\s*=\s*"\K[^"]+' setup.py)
+          echo "New version: $NEW_VERSION"
+          
+          # Get previous version from git history
+          OLD_VERSION=$(git show HEAD~1:./setup.py | grep -oP 'VERSION\s*=\s*"\K[^"]+' || echo "0.0.0")
+          echo "Old version: $OLD_VERSION"
+          
+          if [ "$NEW_VERSION" != "$OLD_VERSION" ]; then
+            echo "Version changed from $OLD_VERSION to $NEW_VERSION"
+            echo "changed=true" >> $GITHUB_OUTPUT
+            echo "new-version=$NEW_VERSION" >> $GITHUB_OUTPUT
+          else
+            echo "Version did not change"
+            echo "changed=false" >> $GITHUB_OUTPUT
+          fi
+
+  build_wheels:
+    name: Build Wheel
+    needs: check-version-change
+    if: ${{ needs.check-version-change.outputs.version-changed == 'true' || github.event_name == 'workflow_dispatch' }}
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+          # Using ubuntu-20.04 instead of 22.04 for more compatibility (glibc). Ideally we'd use the
+          # manylinux docker image, but I haven't figured out how to install CUDA on manylinux.
+          os: [ubuntu-22.04]
+          python-version: ['3.10', '3.11', '3.12', '3.13']
+          # For version reference https://pytorch.org/get-started/previous-versions/
+          torch-cuda:
+            - torch-version: '2.5.1'
+              cuda-version: '12.4.1'
+              torch-cuda-short: 'cu124'
+            - torch-version: '2.6.0'
+              cuda-version: '12.6.3'
+              torch-cuda-short: 'cu126'
+            - torch-version: '2.7.1'
+              cuda-version: '12.8.0'
+              torch-cuda-short: 'cu128'
+
+    steps:
+      - name: Free up disk space
+        run: |
+          echo "Initial disk space:"
+          df -h
+          
+          # Remove large directories
+          sudo rm -rf /usr/share/dotnet
+          sudo rm -rf /usr/local/lib/android
+          sudo rm -rf /opt/ghc
+          sudo rm -rf /usr/local/share/boost
+          sudo rm -rf /usr/share/swift
+          sudo rm -rf /usr/local/lib/node_modules
+          sudo rm -rf /usr/local/share/powershell
+          sudo rm -rf /usr/share/rust
+          sudo rm -rf /usr/local/.ghcup
+          
+          # Remove cached files
+          sudo rm -rf /var/lib/apt/lists/*
+          sudo rm -rf /var/cache/apt/archives/*
+          
+          echo "Disk space after cleanup:"
+          df -h
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install CUDA ${{ matrix.torch-cuda.cuda-version }}
+        uses: Jimver/cuda-toolkit@v0.2.21
+        id: cuda-toolkit
+        with:
+          cuda: ${{ matrix.torch-cuda.cuda-version }}
+          linux-local-args: '["--toolkit"]'
+          method: 'network'
+
+      - name: Install dependencies (GCC, Clang, CUDA Paths, Git)
+        run: |
+          sudo apt update
+          sudo apt install -y git patchelf gcc-11 g++-11 clang-11
+          sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+
+          # Allow Git to Access Safe Directory
+          git config --global --add safe.directory /__w/FastVideo/FastVideo
+
+          # Set CUDA environment variables
+          export CUDA_HOME=/usr/local/cuda-${{ matrix.torch-cuda.cuda-version }}
+          export PATH=${CUDA_HOME}/bin:${PATH}
+          export LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
+          
+          # Verify installation
+          gcc --version
+          g++ --version
+          clang-11 --version
+          nvcc --version
+
+      - name: Install PyTorch ${{ matrix.torch-cuda.torch-version }}+cu${{ matrix.torch-cuda.cuda-version }}
+        run: |
+          pip install --upgrade pip
+          # With python 3.13 and torch 2.5.1, unless we update typing-extensions, we get error
+          # AttributeError: attribute '__default__' of 'typing.ParamSpec' objects is not writable
+          pip install typing-extensions==4.12.2
+          # We want to figure out the CUDA version to download pytorch
+          # e.g. we can have system CUDA version being 11.7 but if torch==1.12 then we need to download the wheel from cu116
+          # see https://github.com/pytorch/pytorch/blob/main/RELEASE.md#release-compatibility-matrix
+          pip install --no-cache-dir torch==${{ matrix.torch-cuda.torch-version }} --index-url https://download.pytorch.org/whl/${{matrix.torch-cuda.torch-cuda-short}}
+          nvcc --version
+          python --version
+          python -c "import torch; print('PyTorch:', torch.__version__)"
+          python -c "import torch; print('CUDA:', torch.version.cuda)"
+          python -c "from torch.utils import cpp_extension; print (cpp_extension.CUDA_HOME)"
+
+      - name: Build wheel
+        run: |
+          export PYTHONPATH=$GITHUB_WORKSPACE:$PYTHONPATH
+          
+          # We want setuptools >= 49.6.0 otherwise we can't compile the extension if system CUDA version is 11.7 and pytorch cuda version is 11.6
+          # https://github.com/pytorch/pytorch/blob/664058fa83f1d8eede5d66418abff6e20bd76ca8/torch/utils/cpp_extension.py#L810
+          # However this still fails so I'm using a newer version of setuptools
+          pip install setuptools
+          pip install ninja packaging wheel
+
+          cd csrc/attn/video_sparse_attn  # Move into the correct folder
+          git submodule update --init --recursive # Ensure ThunderKittens submodule is initialized
+          python setup.py bdist_wheel --dist-dir=dist
+
+      - name: Rename wheel file
+        run: |
+          cd csrc/attn/video_sparse_attn
+
+          CUDA_SHORT_VERSION=$(echo ${{ matrix.torch-cuda.cuda-version }} | cut -d. -f1,2 | sed 's/\.//g')
+          TORCH_SHORT_VERSION=$(echo ${{ matrix.torch-cuda.torch-version }} | cut -d. -f1,2)
+          # Get the correct version format
+          tmpname=cu${CUDA_SHORT_VERSION}torch${TORCH_SHORT_VERSION}
+          wheel_name=$(ls dist/*whl | xargs -n 1 basename | sed "s/-/+$tmpname-/2")
+          # Rename with version information
+          ls dist/*whl |xargs -I {} mv {} dist/${wheel_name}
+          echo "wheel_name=${wheel_name}" >> $GITHUB_ENV
+
+      - name: Upload wheel artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ env.wheel_name }}
+          path: csrc/attn/video_sparse_attn/dist/*.whl
+          retention-days: 90
+
+  publish_package:
+    name: Publish package
+    needs: [build_wheels, check-version-change]
+    if: ${{ needs.check-version-change.outputs.version-changed == 'true' || github.event_name == 'workflow_dispatch' }}
+    runs-on: ubuntu-22.04
+    permissions:
+      id-token: write  # Needed for OIDC Trusted Publishing
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+
+      - name: Install CUDA 12.4.1
+        uses: Jimver/cuda-toolkit@v0.2.21
+        id: cuda-toolkit
+        with:
+          cuda: 12.4.1
+          linux-local-args: '["--toolkit"]'
+          method: 'network'
+          sub-packages: '["nvcc"]'
+
+      - name: Install dependencies (GCC, Clang, CUDA Paths, Git)
+        run: |
+          sudo apt update
+          sudo apt install -y git patchelf gcc-11 g++-11 clang-11
+          sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+
+          # Allow Git to Access Safe Directory
+          git config --global --add safe.directory /__w/FastVideo/FastVideo
+
+          # Set CUDA environment variables
+          export CUDA_HOME=/usr/local/cuda-12.4.1
+          export PATH=${CUDA_HOME}/bin:${PATH}
+          export LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
+          
+          # Verify installation
+          gcc --version
+          g++ --version
+          clang-11 --version
+          nvcc --version
+
+      - name: Install PyTorch 2.5.1+cu12.4.1
+        run: |
+          pip install --upgrade pip
+          # With python 3.13 and torch 2.5.1, unless we update typing-extensions, we get error
+          # AttributeError: attribute '__default__' of 'typing.ParamSpec' objects is not writable
+          pip install typing-extensions==4.12.2
+          # We want to figure out the CUDA version to download pytorch
+          # e.g. we can have system CUDA version being 11.7 but if torch==1.12 then we need to download the wheel from cu116
+          # see https://github.com/pytorch/pytorch/blob/main/RELEASE.md#release-compatibility-matrix
+          export TORCH_CUDA_VERSION=124
+          pip install --no-cache-dir torch==2.5.1 --index-url https://download.pytorch.org/whl/cu${TORCH_CUDA_VERSION}
+          nvcc --version
+          python --version
+          python -c "import torch; print('PyTorch:', torch.__version__)"
+          python -c "import torch; print('CUDA:', torch.version.cuda)"
+          python -c "from torch.utils import cpp_extension; print (cpp_extension.CUDA_HOME)"
+
+      - name: Build source distribution
+        run: |
+          export PYTHONPATH=$GITHUB_WORKSPACE:$PYTHONPATH
+          
+          # We want setuptools >= 49.6.0 otherwise we can't compile the extension if system CUDA version is 11.7 and pytorch cuda version is 11.6
+          # https://github.com/pytorch/pytorch/blob/664058fa83f1d8eede5d66418abff6e20bd76ca8/torch/utils/cpp_extension.py#L810
+          # However this still fails so I'm using a newer version of setuptools
+          pip install setuptools
+          pip install ninja packaging wheel
+
+          cd csrc/attn/video_sparse_attn  # Move into the correct folder
+          git submodule update --init --recursive # Ensure ThunderKittens submodule is initialized
+          python setup.py sdist --dist-dir=dist
+
+      - name: Publish release distributions to PyPI
+        uses: pypa/gh-action-pypi-publish@release/v1
+        with:
+          packages-dir: csrc/attn/video_sparse_attn/dist/

.gitignore

@@ -14,6 +14,8 @@ wandb/
 *.pt
 cache_dir/
 wandb/
+venv/
+.venv/
 runs/
 samples/
 *validation/
@@ -28,6 +30,8 @@ env
 **/build/
 **.pyc
 **.txt
+*.log
+weights/
 
 # Distribution / packaging
 build/
@@ -37,11 +41,13 @@ dist/
 eggs/
 .eggs/
 
-# Sphinx documentation
-docs/_build/
-docs/source/getting_started/examples/
-docs/source/inference/examples/
-docs/source/training/examples/
+# MkDocs documentation
+site/
+docs/getting_started/examples/
+docs/inference/examples/
+docs/training/examples/
+docs/distillation/examples/
+!requirements-mkdocs.txt
 
 # VSCode
 .vscode/
@@ -60,6 +66,9 @@ docs/source/training/examples/
 !fastvideo/tests/ssim/reference_videos/**/*.mp4
 
 # Static images
-!docs/source/_static/images/**/*.png
+!docs/assets/images/**/*.png
 !comfyui/assets/**/*.png
 !comfyui/assets/**/*.gif
+
+dmd_t2v_output/
+preprocess_output_text/

.gitmodules

@@ -1,3 +1,6 @@
-[submodule "csrc/attn/tk"]
-	path = csrc/attn/tk
+[submodule "fastvideo-kernel/include/tk"]
+	path = fastvideo-kernel/include/tk
 	url = https://github.com/HazyResearch/ThunderKittens.git
+[submodule "fastvideo-kernel/include/cutlass"]
+	path = fastvideo-kernel/include/cutlass
+	url = https://github.com/NVIDIA/cutlass.git

.pre-commit-config.yaml

@@ -4,17 +4,15 @@ default_stages:
 exclude: |
   (?x)(
     fastvideo/third_party/.*|
-    csrc/.*|
+    fastvideo-kernel/.*|
     assets/.*|
     tests/.*|
     demo/.*|
     predict\.py|
     scripts/.*|
+    prompts/.*|
     fastvideo/data_preprocess/.*|
     fastvideo/dataset/.*|
-    fastvideo/distill/.*|
-    fastvideo/distill\.py|
-    fastvideo/distill_adv\.py|
     fastvideo/models/.*|
     fastvideo/sample/.*|
     fastvideo/train\.py|
@@ -22,6 +20,7 @@ exclude: |
     examples/.*|
     .github/workflows/fastvideo-publish.yml|
     .github/workflows/sta-publish.yml|
+    .github/workflows/vsa-publish.yml|
     .github/workflows/build-image-template.yml|
     docs/source/inference/support_matrix.md
   )
@@ -43,10 +42,10 @@ repos:
   - id: codespell
     additional_dependencies: ['tomli']
     args: ['--toml', 'pyproject.toml']
-- repo: https://github.com/PyCQA/isort
-  rev: 6.0.1
-  hooks:
-  - id: isort
+# - repo: https://github.com/PyCQA/isort
+#   rev: 6.0.1
+#   hooks:
+#   - id: isort
 - repo: https://github.com/jackdewinter/pymarkdown
   rev: v0.9.30
   hooks:

README.md

@@ -1,42 +1,47 @@
 <div align="center">
-<img src=assets/logo.jpg width="30%"/>
+<img src=assets/logos/logo.svg width="30%"/>
 </div>
 
-**FastVideo is a unified framework for accelerated video generation.**
-
-It features a clean, consistent API that works across popular video models, making it easier for developers to author new models and incorporate system- or kernel-level optimizations.
-With FastVideo's optimizations, you can achieve more than 3x inference improvement compared to other systems.
-
 <p align="center">
-    | <a href="https://hao-ai-lab.github.io/FastVideo"><b>Documentation</b></a> | <a href="https://hao-ai-lab.github.io/FastVideo/inference/inference_quick_start.html"><b> Quick Start</b></a> | 🤗 <a href="https://huggingface.co/FastVideo/FastHunyuan"  target="_blank"><b>FastHunyuan</b></a>  | 🤗 <a href="https://huggingface.co/FastVideo/FastMochi-diffusers" target="_blank"><b>FastMochi</b></a> | 🟣💬 <a href="https://join.slack.com/t/fastvideo/shared_invite/zt-38u6p1jqe-yDI1QJOCEnbtkLoaI5bjZQ" target="_blank"> <b>Slack</b> </a> |
+     | <a href="https://hao-ai-lab.github.io/FastVideo"><b>Documentation</b></a> | <a href="https://hao-ai-lab.github.io/FastVideo/inference/inference_quick_start/"><b> Quick Start</b></a> | <a href="https://github.com/hao-ai-lab/FastVideo/discussions/982"  target="_blank"><b>Weekly Dev Meeting</b></a>  | 🟣💬 <a href="https://join.slack.com/t/fastvideo/shared_invite/zt-3f4lao1uq-u~Ipx6Lt4J27AlD2y~IdLQ" target="_blank"> <b>Slack</b> </a> |  🟣💬 <a href="https://ibb.co/sv3MMKyv" target="_blank"> <b> WeChat </b> </a> |
 </p>
 
-<div align="center">
-<img src=assets/perf.png width="90%"/>
-</div>
+**FastVideo is a unified post-training and inference framework for accelerated video generation.**
 
 ## NEWS
+- ```2025/11/19```: Release [CausalWan2.2 I2V A14B Preview](https://huggingface.co/FastVideo/CausalWan2.2-I2V-A14B-Preview-Diffusers) models, [Blog](https://hao-ai-lab.github.io/blogs/fastvideo_causalwan_preview/) and [Inference Code!](https://github.com/hao-ai-lab/FastVideo/blob/main/examples/inference/basic/basic_self_forcing_causal_wan2_2_i2v.py)
+- ```2025/08/04```: Release [FastWan](https://hao-ai-lab.github.io/FastVideo/distillation/dmd) models and [Sparse-Distillation](https://hao-ai-lab.github.io/blogs/fastvideo_post_training/).
+
+<details>
+<summary>More</summary>
+
 - ```2025/06/14```: Release finetuning and inference code for [VSA](https://arxiv.org/pdf/2505.13389)
 - ```2025/04/24```: [FastVideo V1](https://hao-ai-lab.github.io/blogs/fastvideo/) is released!
 - ```2025/02/18```: Release the inference code for [Sliding Tile Attention](https://hao-ai-lab.github.io/blogs/sta/).
 
+</details>
+
 ## Key Features
 
 FastVideo has the following features:
+- End-to-end post-training support for bidirectional and autoregressive models:
+  - Support full finetuning and LoRA finetuning for state-of-the-art open video DiTs
+  - Data preprocessing pipeline for video, image, and text data
+  - Distribution Matching Distillation (DMD2) stepwise distillation.
+  - Sparse attention with [Video Sparse Attention](https://arxiv.org/pdf/2505.13389)
+  - [Sparse distillation](https://hao-ai-lab.github.io/blogs/fastvideo_post_training/) to achineve >50x denoising speedup
+  - Scalable training with FSDP2, sequence parallelism, and selective activation checkpointing.
+  - Causal distillation through Self-Forcing
+  - See this [page](https://hao-ai-lab.github.io/FastVideo/training/overview/) for full list of supported models and recipes.
 - State-of-the-art performance optimizations for inference
-  - [Sliding Tile Attention](https://arxiv.org/pdf/2502.04507)
-  - [TeaCache](https://arxiv.org/pdf/2411.19108)
-  - [Sage Attention](https://arxiv.org/abs/2410.02367)
-- Cutting edge models
-  - Wan2.1 T2V, I2V
-  - HunyuanVideo
-  - FastHunyuan: consistency distilled video diffusion models for 8x inference speedup.
-  - StepVideo T2V
-- Distillation support
-  - Recipes for video DiT, based on [PCM](https://github.com/G-U-N/Phased-Consistency-Model).
-  - Support distilling/finetuning/inferencing state-of-the-art open video DiTs: 1. Mochi 2. Hunyuan.
-- Scalable training with FSDP, sequence parallelism, and selective activation checkpointing, with near linear scaling to 64 GPUs.
-- Memory efficient finetuning with LoRA, precomputed latent, and precomputed text embeddings.
+  - Sequence Parallelism for distributed inference
+  - Multiple state-of-the-art attention backends
+  - User-friendly CLI and Python API
+  - See this [page](https://hao-ai-lab.github.io/FastVideo/inference/optimizations/) for full list of supported optimizations.
+- Diverse hardware and OS support
+  - Support H100, A100, 4090
+  - Support Linux, Windows, MacOS
+  - See this [page](https://hao-ai-lab.github.io/FastVideo/inference/hardware_support/) for full list of supported hardware and OS.
 
 ## Getting Started
 We recommend using an environment manager such as `Conda` to create a clean environment:
@@ -50,19 +55,33 @@ conda activate fastvideo
 pip install fastvideo
 ```
 
-Please see our [docs](https://hao-ai-lab.github.io/FastVideo/getting_started/installation.html) for more detailed installation instructions.
+Please see our [docs](https://hao-ai-lab.github.io/FastVideo/getting_started/installation/) for more detailed installation instructions.
+
+## Sparse Distillation
+For our sparse distillation techniques, please see our [distillation docs](https://hao-ai-lab.github.io/FastVideo/distillation/dmd/) and check out our [blog](https://hao-ai-lab.github.io/blogs/fastvideo_post_training/).
+
+See below for recipes and datasets:
+
+|                                            Model                                              |                                               Sparse Distillation                                                 |                                                  Dataset                                                  |
+|:-------------------------------------------------------------------------------------------:  |:---------------------------------------------------------------------------------------------------------------:  |:--------------------------------------------------------------------------------------------------------: |
+| [FastWan2.1-T2V-1.3B](https://huggingface.co/FastVideo/FastWan2.1-T2V-1.3B-Diffusers)         |    [Recipe](https://github.com/hao-ai-lab/FastVideo/tree/main/examples/distill/Wan2.1-T2V/Wan-Syn-Data-480P)      | [FastVideo Synthetic Wan2.1 480P](https://huggingface.co/datasets/FastVideo/Wan-Syn_77x448x832_600k)      |
+| [FastWan2.1-T2V-14B-Preview](https://huggingface.co/FastVideo/FastWan2.1-T2V-14B-Diffusers)   |                                                   Coming soon!                                                    |   [FastVideo Synthetic Wan2.1 720P](https://huggingface.co/datasets/FastVideo/Wan-Syn_77x768x1280_250k)   |
+| [FastWan2.2-TI2V-5B](https://huggingface.co/FastVideo/FastWan2.2-TI2V-5B-Diffusers)           | [Recipe](https://github.com/hao-ai-lab/FastVideo/tree/main/examples/distill/Wan2.2-TI2V-5B-Diffusers/Data-free)   | [FastVideo Synthetic Wan2.2 720P](https://huggingface.co/datasets/FastVideo/Wan2.2-Syn-121x704x1280_32k)  |
 
 ## Inference
 ### Generating Your First Video
-Here's a minimal example to generate a video using the default settings. Create a file called `example.py` with the following code:
+Here's a minimal example to generate a video using the default settings. Make sure VSA kernels are [installed](https://hao-ai-lab.github.io/FastVideo/video_sparse_attention/installation/). Create a file called `example.py` with the following code:
 
 ```python
+import os
 from fastvideo import VideoGenerator
 
 def main():
+    os.environ["FASTVIDEO_ATTENTION_BACKEND"] = "VIDEO_SPARSE_ATTN"
+
     # Create a video generator with a pre-trained model
     generator = VideoGenerator.from_pretrained(
-        "Wan-AI/Wan2.1-T2V-1.3B-Diffusers",
+        "FastVideo/FastWan2.1-T2V-1.3B-Diffusers",
         num_gpus=1,  # Adjust based on your hardware
     )
 
@@ -87,77 +106,68 @@ Run the script with:
 python example.py
 ```
 
-For a more detailed guide, please see our [inference quick start](https://hao-ai-lab.github.io/FastVideo/inference/inference_quick_start.html).
+For a more detailed guide, please see our [inference quick start](https://hao-ai-lab.github.io/FastVideo/inference/inference_quick_start/).
 
 ### Other docs:
 
-- [Design Overview](https://hao-ai-lab.github.io/FastVideo/design/overview.html)
-- [Contribution Guide](https://hao-ai-lab.github.io/FastVideo/getting_started/installation.html)
+- [Design Overview](https://hao-ai-lab.github.io/FastVideo/design/overview/)
+- [Contribution Guide](https://hao-ai-lab.github.io/FastVideo/getting_started/installation/)
 
 ## Distillation and Finetuning
-- [Distillation Guide](https://hao-ai-lab.github.io/FastVideo/training/distillation.html)
-- [Finetuning Guide](https://hao-ai-lab.github.io/FastVideo/training/finetune.html)
+- [Distillation Guide](https://hao-ai-lab.github.io/FastVideo/distillation/dmd/)
+<!-- - [Finetuning Guide](https://hao-ai-lab.github.io/FastVideo/training/finetune.html) -->
 
-## 📑 Development Plan
+## Awesome work using FastVideo or our research projects
 
-<!-- - More distillation methods -->
-  <!-- - [ ] Add Distribution Matching Distillation -->
-- More models support
-  <!-- - [ ] Add CogvideoX model -->
-  - [x] Add StepVideo to V1
-- Optimization features
-  - [x] Teacache in V1
-  - [x] SageAttention in V1
-- Code updates
-  - [x] V1 Configuration API
-  - [ ] Support Training in V1
-  <!-- - [ ] fp8 support -->
-  <!-- - [ ] faster load model and save model support -->
+- [SGLang](https://github.com/sgl-project/sglang/tree/main/python/sglang/multimodal_gen): SGLang's diffusion inference functionality is based  on a fork of FastVideo on Sept. 24, 2025. [![Star](https://img.shields.io/github/stars/sgl-project/sglang.svg?style=social&label=Star)](https://github.com/sgl-project/sglang)
+
+- [DanceGRPO](https://github.com/XueZeyue/DanceGRPO): A  unified framework to adapt Group Relative Policy Optimization (GRPO) to visual generation paradigms. Code based on FastVideo. [![Star](https://img.shields.io/github/stars/XueZeyue/DanceGRPO.svg?style=social&label=Star)](https://github.com/XueZeyue/DanceGRPO)
+- [SRPO](https://github.com/Tencent-Hunyuan/SRPO): A method to directly align the full diffusion trajectory with fine-grained human preference. Code based on FastVideo. [![Star](https://img.shields.io/github/stars/Tencent-Hunyuan/SRPO.svg?style=social&label=Star)](https://github.com/Tencent-Hunyuan/SRPO)
+- [DCM](https://github.com/Vchitect/DCM): Dual-expert consistency model for efficient and high-quality video generation. Code based on FastVideo. [![Star](https://img.shields.io/github/stars/Vchitect/DCM.svg?style=social&label=Star)](https://github.com/Vchitect/DCM)
+- [Hunyuan Video 1.5](https://github.com/Tencent-Hunyuan/HunyuanVideo-1.5): A leading lightweight video generation model, where they proposed SSTA based on Sliding Tile Attention. [![Star](https://img.shields.io/github/stars/Tencent-Hunyuan/HunyuanVideo-1.5.svg?style=social&label=Star)](https://github.com/Tencent-Hunyuan/HunyuanVideo-1.5)
+- [Kandinsky-5.0](https://github.com/kandinskylab/kandinsky-5): A family of diffusion models for video & image generation, where their NABLA attention includes a Sliding Tile Attention branch. [![Star](https://img.shields.io/github/stars/kandinskylab/kandinsky-5.svg?style=social&label=Star)](https://github.com/kandinskylab/kandinsky-5)
+- [LongCat Video](https://github.com/meituan-longcat/LongCat-Video): A foundational video generation model with 13.6B parameters with block-sparse attention similar to Video Sparse Attention. [![Star](https://img.shields.io/github/stars/meituan-longcat/LongCat-Video.svg?style=social&label=Star)](https://github.com/meituan-longcat/LongCat-Video)
 
 ## 🤝 Contributing
 
-We welcome all contributions. Please check out our guide [here](https://hao-ai-lab.github.io/FastVideo/contributing/overview.html)
-
+We welcome all contributions. Please check out our guide [here](https://hao-ai-lab.github.io/FastVideo/contributing/overview/).
+See details in [development roadmap](https://github.com/hao-ai-lab/FastVideo/issues/899).
 ## Acknowledgement
 We learned and reused code from the following projects:
-- [PCM](https://github.com/G-U-N/Phased-Consistency-Model)
+- [Wan-Video](https://github.com/Wan-Video)
+- [ThunderKittens](https://github.com/HazyResearch/ThunderKittens)
+- [Triton](https://github.com/triton-lang/triton)
+- [DMD2](https://github.com/tianweiy/DMD2)
 - [diffusers](https://github.com/huggingface/diffusers)
-- [OpenSoraPlan](https://github.com/PKU-YuanGroup/Open-Sora-Plan)
 - [xDiT](https://github.com/xdit-project/xDiT)
 - [vLLM](https://github.com/vllm-project/vllm)
 - [SGLang](https://github.com/sgl-project/sglang)
 
-We thank MBZUAI and [Anyscale](https://www.anyscale.com/) for their support throughout this project.
+We thank [MBZUAI](https://ifm.mbzuai.ac.ae/), [Anyscale](https://www.anyscale.com/), and [GMI Cloud](https://www.gmicloud.ai/) for their support throughout this project.
 
 ## Citation
-If you use FastVideo for your research, please cite our paper:
+If you find FastVideo useful, please considering citing our work:
 
 ```bibtex
-@misc{zhang2025vsafastervideodiffusion,
-      title={VSA: Faster Video Diffusion with Trainable Sparse Attention}, 
-      author={Peiyuan Zhang and Haofeng Huang and Yongqi Chen and Will Lin and Zhengzhong Liu and Ion Stoica and Eric Xing and Hao Zhang},
-      year={2025},
-      eprint={2505.13389},
-      archivePrefix={arXiv},
-      primaryClass={cs.CV},
-      url={https://arxiv.org/abs/2505.13389}, 
+@software{fastvideo2024,
+  title        = {FastVideo: A Unified Framework for Accelerated Video Generation},
+  author       = {The FastVideo Team},
+  url          = {https://github.com/hao-ai-lab/FastVideo},
+  month        = apr,
+  year         = {2024},
 }
-@misc{zhang2025fastvideogenerationsliding,
-      title={Fast Video Generation with Sliding Tile Attention},
-      author={Peiyuan Zhang and Yongqi Chen and Runlong Su and Hangliang Ding and Ion Stoica and Zhenghong Liu and Hao Zhang},
-      year={2025},
-      eprint={2502.04507},
-      archivePrefix={arXiv},
-      primaryClass={cs.CV},
-      url={https://arxiv.org/abs/2502.04507},
+
+@article{zhang2025vsa,
+  title={Vsa: Faster video diffusion with trainable sparse attention},
+  author={Zhang, Peiyuan and Chen, Yongqi and Huang, Haofeng and Lin, Will and Liu, Zhengzhong and Stoica, Ion and Xing, Eric and Zhang, Hao},
+  journal={arXiv preprint arXiv:2505.13389},
+  year={2025}
 }
-@misc{ding2025efficientvditefficientvideodiffusion,
-      title={Efficient-vDiT: Efficient Video Diffusion Transformers With Attention Tile},
-      author={Hangliang Ding and Dacheng Li and Runlong Su and Peiyuan Zhang and Zhijie Deng and Ion Stoica and Hao Zhang},
-      year={2025},
-      eprint={2502.06155},
-      archivePrefix={arXiv},
-      primaryClass={cs.CV},
-      url={https://arxiv.org/abs/2502.06155},
+
+@article{zhang2025fast,
+  title={Fast video generation with sliding tile attention},
+  author={Zhang, Peiyuan and Chen, Yongqi and Su, Runlong and Ding, Hangliang and Stoica, Ion and Liu, Zhengzhong and Zhang, Hao},
+  journal={arXiv preprint arXiv:2502.04507},
+  year={2025}
 }
 ```

__init__.py

@@ -0,0 +1,15 @@
+try:
+    from .comfyui.video_generator.nodes import (NODE_CLASS_MAPPINGS,
+                                                NODE_DISPLAY_NAME_MAPPINGS)
+    WEB_DIRECTORY = "./web"
+    __all__ = [
+        'NODE_CLASS_MAPPINGS', 'NODE_DISPLAY_NAME_MAPPINGS', 'WEB_DIRECTORY'
+    ]
+except ImportError:
+    # ComfyUI environment not available, skip comfyui imports
+    NODE_CLASS_MAPPINGS = {}
+    NODE_DISPLAY_NAME_MAPPINGS = {}
+    WEB_DIRECTORY = "./web"
+    __all__ = [
+        'NODE_CLASS_MAPPINGS', 'NODE_DISPLAY_NAME_MAPPINGS', 'WEB_DIRECTORY'
+    ]

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benchmarks/fvd/README.md

@@ -0,0 +1,106 @@
+# FVD (Fréchet Video Distance) Benchmark
+
+Evaluate generated video quality using FVD with the I3D feature extractor.
+
+## Quick Start
+
+**Run the benchmark:**
+
+```bash
+bash benchmarks/scripts/run.sh
+```
+
+That's it! The script auto-installs dependencies and runs the benchmark.
+
+**To customize:** Edit `benchmarks/fvd/run_fvd.py` to change:
+- Video paths (`real_dir`, `gen_dir`)
+- Number of videos, frames, sampling strategy
+- Device, batch size, caching, etc.
+
+## Advanced Usage (CLI)
+
+For more control without editing Python files, use the CLI.
+
+**First-time setup** (one-time per pod/environment):
+
+```bash
+bash benchmarks/scripts/setup_fvd.sh
+```
+
+Then run any configuration you want:
+
+```bash
+# Custom configuration
+python -m benchmarks.fvd.cli \
+    --real-path data/real/ \
+    --gen-path outputs/gen/ \
+    --num-videos 1024 \
+    --num-frames 32 \
+    --clip-strategy random \
+    --batch-size 32 \
+    --seed 42 \
+    --extractor clip
+```
+
+**Standard protocols:**
+
+```bash
+# Use predefined protocols
+python -m benchmarks.fvd.cli \
+    --real-path data/real/ \
+    --gen-path outputs/gen/ \
+    --protocol fvd2048_16f  # or fvd2048_128f, quick_test, etc.
+```
+
+This would use i3d model by default as the feature extractor
+
+**Feature caching** (speed up repeated evaluations):
+
+```bash
+python -m benchmarks.fvd.cli \
+    --real-path data/real/ \
+    --gen-path outputs/gen/ \
+    --protocol fvd2048_16f \
+    --cache-real-features fvd-cache/extractor_name  # Directory path (will save/load fvd-cache/extractor_name/extractor-name_real_features.pkl)
+```
+
+Run `python -m benchmarks.fvd.cli --help` for all options.
+
+## Available Protocols
+
+- `fvd2048_16f` - Standard (2048 videos, 16 frames)
+- `fvd2048_128f` - Long videos (128 frames)
+- `fvd2048_128f_subsample8` - Subsampled long videos
+- `quick_test` - Fast testing (10 videos)
+
+## Configuration Options
+
+Key options in `FVDConfig`:
+
+```python
+num_videos=2048,              # Videos to evaluate
+num_frames_per_clip=16,       # Frames per clip
+clip_strategy='beginning',    # beginning|random|uniform|middle|sliding
+frame_stride=1,               # Frame subsampling
+batch_size=32,                # GPU batch size
+device='cuda',                # cuda|cpu
+cache_real_features=None,     # Cache path for speed
+seed=42,                      # Reproducibility
+extractor='i3d',              # i3d|clip|videomae
+```
+
+## Programmatic Usage
+
+```python
+from benchmarks.fvd import compute_fvd_with_config, FVDConfig
+
+config = FVDConfig.fvd2048_16f()  # or custom config
+results = compute_fvd_with_config('data/real/', 'outputs/gen/', config)
+print(f"FVD: {results['fvd']:.2f}")
+```
+
+## Notes
+
+- Requires minimum 10 frames per clip
+- Supports both video files (.mp4, .avi, etc.) and frame directories
+- `--cache-real-features` expects a **directory path** (e.g., `cache/real`), it will automatically create/load `real_features.pkl` inside that directory

benchmarks/fvd/__init__.py

@@ -0,0 +1,38 @@
+"""
+FastVideo Frechet Video Distance (FVD) Benchmark Module.
+    >>> from fastvideo.benchmarks.fvd import compute_fvd_with_config, FVDConfig
+    >>> config = FVDConfig.fvd2048_16f()  # Standard protocol
+    >>> results = compute_fvd_with_config('data/real/', 'outputs/gen/', config)
+    >>> print(f"FVD: {results['fvd']:.2f}")
+"""
+
+from .fvd import (
+    compute_fvd,
+    compute_fvd_with_config,
+    compute_frechet_distance,
+    compute_statistics,
+    FVDConfig,
+)
+from .feature_extractors import (BaseFeatureExtractor, I3DFeatureExtractor,
+                                 load_extractor)
+from .video_utils import (
+    load_video_auto,
+    sample_clips_from_video,
+    load_video_clips_streaming,
+    ClipSamplingStrategy,
+)
+
+__all__ = [
+    'compute_fvd',
+    'compute_fvd_with_config',
+    'compute_frechet_distance',
+    'compute_statistics',
+    'FVDConfig',
+    'BaseFeatureExtractor',
+    'I3DFeatureExtractor',
+    'load_extractor',
+    'load_video_auto',
+    'sample_clips_from_video',
+    'load_video_clips_streaming',
+    'ClipSamplingStrategy',
+]

benchmarks/fvd/cli.py

@@ -0,0 +1,107 @@
+import argparse
+import sys
+import traceback
+from .fvd import compute_fvd_with_config, FVDConfig
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(
+        description='Compute Fréchet Video Distance (FVD)')
+
+    # Required arguments
+    parser.add_argument('--real-path',
+                        type=str,
+                        required=True,
+                        help='Path to real videos')
+    parser.add_argument('--gen-path',
+                        type=str,
+                        required=True,
+                        help='Path to generated videos')
+
+    # Extractor selection
+    parser.add_argument('--extractor',
+                        type=str,
+                        default='i3d',
+                        choices=['i3d', 'clip', 'videomae'],
+                        help='Feature extractor model to use (default: i3d)')
+
+    # Standard args
+    parser.add_argument('--seed',
+                        type=int,
+                        default=None,
+                        help='Random seed for reproducibility')
+    parser.add_argument('--protocol',
+                        type=str,
+                        default=None,
+                        choices=['fvd2048_16f', 'fvd2048_128f', 'quick_test'],
+                        help='Use standard protocol (overrides other settings)')
+    parser.add_argument('--num-videos',
+                        type=int,
+                        default=2048,
+                        help='Number of videos to use')
+    parser.add_argument('--num-frames',
+                        type=int,
+                        default=16,
+                        help='Number of frames per clip')
+    parser.add_argument('--clip-strategy',
+                        type=str,
+                        default='beginning',
+                        help='Clip sampling strategy')
+    parser.add_argument('--batch-size',
+                        type=int,
+                        default=32,
+                        help='Batch size for feature extraction')
+    parser.add_argument('--device',
+                        type=str,
+                        default='cuda',
+                        help='Device to use (cuda or cpu)')
+    parser.add_argument('--cache-real-features',
+                        type=str,
+                        default=None,
+                        help='Path to cache real video features')
+    parser.add_argument('--quiet',
+                        action='store_true',
+                        help='Suppress progress output')
+
+    args = parser.parse_args()
+
+    # Create config
+    if args.protocol:
+        protocol_map = {
+            'fvd2048_16f': FVDConfig.fvd2048_16f,
+            'fvd2048_128f': FVDConfig.fvd2048_128f,
+            'quick_test': FVDConfig.quick_test,
+        }
+        config = protocol_map[args.protocol]()
+        # Apply overrides
+        config.device = args.device
+        config.cache_real_features = args.cache_real_features
+        config.extractor_model = args.extractor  # Apply extractor arg
+    else:
+        config = FVDConfig(
+            num_videos=args.num_videos,
+            num_frames_per_clip=args.num_frames,
+            extractor_model=args.extractor,  # Apply extractor arg
+            clip_strategy=args.clip_strategy,
+            batch_size=args.batch_size,
+            device=args.device,
+            cache_real_features=args.cache_real_features,
+            seed=args.seed)
+
+    try:
+        _ = compute_fvd_with_config(
+            args.real_path,  # noqa: F841
+            args.gen_path,
+            config,
+            verbose=not args.quiet)
+
+        return 0
+
+    except Exception as e:
+        print(f"Error: {e}", file=sys.stderr)
+        traceback.print_exc(file=sys.stderr)
+        return 1
+
+
+if __name__ == '__main__':
+    sys.exit(main())

benchmarks/fvd/feature_extractors.py

@@ -0,0 +1,264 @@
+"""
+Pluggable Feature Extractors for FVD Computation.
+Supports I3D (standard), CLIP, and VideoMAE via a common interface.
+"""
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from abc import ABC, abstractmethod
+from huggingface_hub import hf_hub_download
+from tqdm import tqdm
+
+try:
+    from transformers import CLIPModel, CLIPProcessor, VideoMAEModel
+    TRANSFORMERS_AVAILABLE = True
+except ImportError:
+    TRANSFORMERS_AVAILABLE = False
+
+
+class BaseFeatureExtractor(ABC, nn.Module):
+    """Abstract base class for all video feature extractors."""
+
+    def __init__(self, device: str = 'cuda'):
+        super().__init__()
+        self.device = torch.device(
+            device if torch.cuda.is_available() else 'cpu')
+
+    @property
+    @abstractmethod
+    def feature_dim(self) -> int:
+        """Dimension of the output feature vector."""
+        pass
+
+    @abstractmethod
+    def preprocess(self, videos: torch.Tensor) -> torch.Tensor:
+        """
+        Args:
+            videos: [B, T, C, H, W] in [0, 255] range.
+        Returns:
+            Preprocessed tensor ready for the model.
+        """
+        pass
+
+    @abstractmethod
+    def extract_features_batch(self, videos: torch.Tensor) -> torch.Tensor:
+        """
+        Extract features for a single batch.
+        Args:
+            videos: [B, T, C, H, W] (raw input)
+        Returns:
+            Features: [B, feature_dim]
+        """
+        pass
+
+    @torch.no_grad()
+    def extract_features(self,
+                         videos: torch.Tensor,
+                         batch_size: int = 32,
+                         verbose: bool = True) -> torch.Tensor:
+        """
+        Extract features for a large tensor of videos by batching.
+        """
+        N = len(videos)
+        all_features = []
+
+        iterator = range(0, N, batch_size)
+        if verbose:
+            iterator = tqdm(
+                iterator,
+                desc=f"Extracting features ({self.__class__.__name__})")
+
+        for i in iterator:
+            batch = videos[i:i + batch_size].to(self.device)
+            features = self.extract_features_batch(batch)
+            all_features.append(features.cpu())
+
+        return torch.cat(all_features, dim=0)
+
+
+# 1. I3D Extractor (The Standard FVD Metric)
+class I3DFeatureExtractor(BaseFeatureExtractor):
+    REPO_ID = 'flateon/FVD-I3D-torchscript'
+    MODEL_FILENAME = 'i3d_torchscript.pt'
+
+    def __init__(self, device: str = 'cuda', cache_dir: str | None = None):
+        super().__init__(device)
+        self.cache_dir = cache_dir
+        self.model = self._load_model()
+        self.model.eval()
+        self.model.to(self.device)
+
+    @property
+    def feature_dim(self) -> int:
+        return 400
+
+    def _load_model(self) -> torch.nn.Module:
+        try:
+            model_path = hf_hub_download(repo_id=self.REPO_ID,
+                                         filename=self.MODEL_FILENAME,
+                                         cache_dir=self.cache_dir)
+            return torch.jit.load(model_path, map_location=self.device)
+        except Exception as e:
+            raise RuntimeError(f"Failed to load I3D model: {e}") from e
+
+    def preprocess(self, videos: torch.Tensor) -> torch.Tensor:
+        """Standard I3D preprocessing: Resize to 224, Norm to [-1, 1]."""
+        B, T, C, H, W = videos.shape
+
+        if T < 10:
+            raise ValueError(f"I3D requires at least 10 frames, got {T}")
+
+        # Normalize to [0, 1]
+        if videos.max() > 1.0:
+            videos = videos / 255.0
+
+        # Scale to [-1, 1]
+        videos = videos * 2.0 - 1.0
+
+        # Resize to 224x224
+        if H != 224 or W != 224:
+            videos = videos.reshape(B * T, C, H, W)
+            videos = F.interpolate(videos,
+                                   size=(224, 224),
+                                   mode='bilinear',
+                                   align_corners=False)
+            videos = videos.reshape(B, T, C, 224, 224)
+
+        # [B, T, C, H, W] -> [B, C, T, H, W]
+        return videos.permute(0, 2, 1, 3, 4).contiguous()
+
+    def extract_features_batch(self, videos: torch.Tensor) -> torch.Tensor:
+        batch = self.preprocess(videos)
+        # TorchScript I3D returns raw logits when return_features=True
+        return self.model(batch,
+                          rescale=False,
+                          resize=False,
+                          return_features=True)
+
+
+# 2. CLIP Extractor (Semantic/Content Quality)
+class CLIPFeatureExtractor(BaseFeatureExtractor):
+
+    def __init__(self,
+                 device: str = 'cuda',
+                 model_name: str = "openai/clip-vit-base-patch32"):
+        if not TRANSFORMERS_AVAILABLE:
+            raise ImportError(
+                "Please install transformers: pip install transformers")
+        super().__init__(device)
+        self.processor = CLIPProcessor.from_pretrained(model_name)
+        self.model = CLIPModel.from_pretrained(model_name).to(self.device)
+        self.model.eval()
+        self._feature_dim = self.model.config.projection_dim
+
+    @property
+    def feature_dim(self) -> int:
+        return self._feature_dim
+
+    def preprocess(self, videos: torch.Tensor) -> torch.Tensor:
+        # Ensure values are [0, 255]
+        if videos.max() <= 1.0:
+            videos = videos * 255.0
+
+        return videos.to(torch.uint8)
+
+    def extract_features_batch(self, videos: torch.Tensor) -> torch.Tensor:
+        # Input: [B, T, C, H, W]
+        B, T, C, H, W = videos.shape
+        videos = self.preprocess(videos)
+
+        # Flatten B*T to treat frames as images
+        images = videos.view(B * T, C, H, W)
+
+        # HF Processor
+        inputs = self.processor(images=images,
+                                return_tensors="pt",
+                                padding=True)
+        inputs = {k: v.to(self.device) for k, v in inputs.items()}
+
+        # Extract features [B*T, Dim]
+        outputs = self.model.get_image_features(**inputs)
+
+        # Reshape [B, T, Dim] and Average Pooling over time
+        outputs = outputs.view(B, T, -1)
+        return outputs.mean(dim=1)
+
+
+# 3. VideoMAE Extractor (Structure/Motion Quality)
+class VideoMAEFeatureExtractor(BaseFeatureExtractor):
+
+    def __init__(self,
+                 device: str = 'cuda',
+                 model_name: str = "MCG-NJU/videomae-base"):
+        if not TRANSFORMERS_AVAILABLE:
+            raise ImportError(
+                "Please install transformers: pip install transformers")
+        super().__init__(device)
+        self.model = VideoMAEModel.from_pretrained(model_name).to(self.device)
+        self.model.eval()
+
+        self.register_buffer(
+            'mean',
+            torch.tensor([0.485, 0.456, 0.406],
+                         device=self.device).view(1, 1, 3, 1, 1))
+        self.register_buffer(
+            'std',
+            torch.tensor([0.229, 0.224, 0.225],
+                         device=self.device).view(1, 1, 3, 1, 1))
+
+    @property
+    def feature_dim(self) -> int:
+        return self.model.config.hidden_size
+
+    def preprocess(self, videos: torch.Tensor) -> torch.Tensor:
+        """
+        Efficient GPU-based preprocessing.
+        Input: [B, T, C, H, W] in range [0, 255]
+        """
+        B, T, C, H, W = videos.shape
+
+        # 1. Resize to 224x224
+        if H != 224 or W != 224:
+            videos = videos.view(B * T, C, H, W)
+            videos = F.interpolate(videos,
+                                   size=(224, 224),
+                                   mode='bilinear',
+                                   align_corners=False)
+            videos = videos.view(B, T, C, 224, 224)
+
+        # 2. Normalize to [0, 1]
+        if videos.dtype != torch.float32:
+            videos = videos.float()
+
+        if videos.max() > 1.0:
+            videos = videos / 255.0
+
+        # 3. Apply ImageNet Mean/Std
+        return (videos - self.mean) / self.std
+
+    def extract_features_batch(self, videos: torch.Tensor) -> torch.Tensor:
+        # Input: [B, T, C, H, W]
+
+        # Fast GPU Preprocessing
+        pixel_values = self.preprocess(videos)
+
+        # Forward pass
+        outputs = self.model(pixel_values)
+
+        # Global Average Pooling of last hidden state [B, T_patches, 768] -> [B, 768]
+        return outputs.last_hidden_state.mean(dim=1)
+
+
+# Factory
+def load_extractor(name: str, device: str = 'cuda') -> BaseFeatureExtractor:
+    name = name.lower()
+    if name == 'i3d':
+        return I3DFeatureExtractor(device)
+    elif name == 'clip':
+        return CLIPFeatureExtractor(device)
+    elif name == 'videomae':
+        return VideoMAEFeatureExtractor(device)
+    else:
+        raise ValueError(
+            f"Unknown extractor: {name}. Options: i3d, clip, videomae")

benchmarks/fvd/fvd.py

@@ -0,0 +1,405 @@
+import numpy as np
+import scipy.linalg
+import torch
+from pathlib import Path
+from collections.abc import Iterator
+import pickle
+from dataclasses import dataclass, field
+from .feature_extractors import BaseFeatureExtractor, load_extractor
+from .video_utils import ClipSamplingStrategy, load_video_clips_streaming
+
+
+def compute_statistics(features: np.ndarray) -> tuple[np.ndarray, np.ndarray]:
+    """Compute mean and covariance."""
+    mu = np.mean(features, axis=0)
+    sigma = np.cov(features, rowvar=False)
+    return mu, sigma
+
+
+def compute_frechet_distance(mu1: np.ndarray,
+                             sigma1: np.ndarray,
+                             mu2: np.ndarray,
+                             sigma2: np.ndarray,
+                             eps: float = 1e-6) -> float:
+    """
+    Compute Fréchet distance between two Gaussians.
+    """
+    sigma1 = sigma1 + eps * np.eye(sigma1.shape[0])
+    sigma2 = sigma2 + eps * np.eye(sigma2.shape[0])
+
+    diff = mu1 - mu2
+    mean_distance = np.sum(diff**2)
+
+    trace_sum = np.trace(sigma1 + sigma2)
+
+    covmean = scipy.linalg.sqrtm(sigma1 @ sigma2)
+
+    if np.iscomplexobj(covmean):
+        if not np.allclose(np.diagonal(covmean).imag, 0, atol=1e-3):
+            print(
+                f"Warning: Imaginary component: {np.max(np.abs(covmean.imag))}")
+        covmean = covmean.real
+
+    trace_product = np.trace(covmean)
+
+    fvd = mean_distance + trace_sum - 2 * trace_product
+
+    return float(fvd)
+
+
+@dataclass
+class FVDConfig:
+    # default configuration for FVD computation:
+
+    # Video selection
+    num_videos: int = 2048
+
+    # Feature Extractor Selection
+    extractor_model: str = 'i3d'  # Options: 'i3d', 'clip', 'videomae'
+
+    # Clip sampling
+    num_frames_per_clip: int = 16
+    num_clips_per_video: int = 1
+    clip_strategy: str | ClipSamplingStrategy = 'beginning'
+
+    # Temporal subsampling
+    frame_stride: int = 1  # 1=no subsampling, 2=every 2nd, 8=every 8th
+    temporal_stride: int = 1  # For sliding window clips
+
+    # Data processing
+    video_extensions: list[str] = field(
+        default_factory=lambda: ['.mp4', '.avi', '.mov', '.mkv'])
+    support_frame_dirs: bool = True
+
+    # Computation
+    batch_size: int = 32
+    device: str = 'cuda'
+
+    use_streaming: bool = True
+    resize_before_extraction: bool = True
+
+    # Caching
+    cache_real_features: str | None = None
+    i3d_model_path: str | None = None
+
+    # Reproducibility
+    seed: int | None = None
+
+    @classmethod
+    def fvd2048_16f(cls) -> 'FVDConfig':
+        """Standard FVD protocol: 2048 videos, 16 frames, beginning clip."""
+        return cls(num_videos=2048,
+                   num_frames_per_clip=16,
+                   clip_strategy='beginning',
+                   use_streaming=True)
+
+    @classmethod
+    def fvd2048_128f(cls) -> 'FVDConfig':
+        """Long video protocol: 2048 videos, 128 frames."""
+        return cls(num_videos=2048,
+                   num_frames_per_clip=128,
+                   clip_strategy='beginning',
+                   use_streaming=True)
+
+    @classmethod
+    def quick_test(cls) -> 'FVDConfig':
+        """Quick test config: 100 videos, 16 frames."""
+        return cls(num_videos=100,
+                   num_frames_per_clip=16,
+                   clip_strategy='beginning')
+
+    def to_dict(self) -> dict:
+        """Export config to dict for logging"""
+        d = self.__dict__.copy()
+        d['clip_strategy'] = str(self.clip_strategy)
+        return d
+
+    def __str__(self) -> str:
+        """Human-readable protocol name"""
+        desc = f"FVD_{self.extractor_model.upper()}_{self.num_videos}_{self.num_frames_per_clip}f"
+        if self.frame_stride > 1:
+            desc += f"_subsample{self.frame_stride}"
+        if self.num_clips_per_video > 1:
+            desc += f"_{self.num_clips_per_video}clips"
+        if self.clip_strategy != 'beginning':
+            desc += f"_{self.clip_strategy}"
+        return desc
+
+
+def extract_features_streaming(video_generator: Iterator[torch.Tensor],
+                               extractor: BaseFeatureExtractor,
+                               batch_size: int = 32,
+                               max_clips: int | None = None,
+                               verbose: bool = True) -> np.ndarray:
+    """
+    Extract features from a video clip generator using streaming.
+    """
+    all_features = []
+    batch = []
+
+    if verbose:
+        print(f"Extracting features with batch_size={batch_size}...")
+
+    with torch.no_grad():
+        for clip_count, clip in enumerate(video_generator):
+            batch.append(clip)
+
+            # Process batch when full
+            if len(batch) == batch_size:
+                batch_tensor = torch.stack(batch).to(extractor.device)
+                features = extractor.extract_features_batch(batch_tensor)
+
+                all_features.append(features.detach().cpu().numpy())
+                batch = []
+
+                if verbose and clip_count % (batch_size * 10) == 0:
+                    print(f"Processed {clip_count} clips...")
+
+            if max_clips is not None and clip_count >= max_clips:
+                break
+
+        # Process remaining clips
+        if len(batch) > 0:
+            batch_tensor = torch.stack(batch).to(extractor.device)
+            features = extractor.extract_features_batch(batch_tensor)
+            all_features.append(features.detach().cpu().numpy())
+
+    if len(all_features) == 0:
+        raise RuntimeError("No features extracted - check video loading")
+
+    features = np.concatenate(all_features, axis=0)
+
+    if verbose:
+        print(f"Extracted {len(features)} feature vectors")
+
+    return features
+
+
+def load_or_compute_features(videos: str | Path | torch.Tensor,
+                             extractor: BaseFeatureExtractor,
+                             config: FVDConfig,
+                             cache_path: str | None = None,
+                             cache_name: str = "real_features") -> np.ndarray:
+    """Load features from cache or compute (with streaming support)"""
+
+    if cache_path is not None:
+        script_dir = Path(__file__).parent
+        cache_dir = script_dir / cache_path
+        cache_file = cache_dir / f"{config.extractor_model}_{cache_name}.pkl"
+
+        if cache_file.exists():
+            print(f"Loading cached features from {cache_file}")
+            with open(cache_file, 'rb') as f:
+                features = pickle.load(f)
+
+            # Validate and limit based on config
+            max_features = config.num_videos * config.num_clips_per_video
+
+            if len(features) < max_features:
+                print(
+                    f"WARNING: Cache has {len(features)} features but need {max_features}"
+                )
+                print("Cached features insufficient - will recompute...")
+            elif len(features) > max_features:
+                print(
+                    f"Using {max_features} features from cache (truncated from {len(features)})"
+                )
+                features = features[:max_features]
+                return features
+            else:
+                print(f"Using all {len(features)} cached features")
+                return features
+
+    print("Computing features from scratch...")
+
+    if isinstance(videos, (str | Path)):
+        target_size = (224, 224) if config.resize_before_extraction else None
+
+        video_generator = load_video_clips_streaming(
+            videos,
+            num_frames=config.num_frames_per_clip,
+            max_videos=config.num_videos,
+            clip_strategy=config.clip_strategy,
+            frame_stride=config.frame_stride,
+            num_clips_per_video=config.num_clips_per_video,
+            video_extensions=config.video_extensions,
+            support_frame_dirs=config.support_frame_dirs,
+            target_size=target_size,
+            verbose=True)
+
+        max_clips = config.num_videos * config.num_clips_per_video
+        features = extract_features_streaming(video_generator,
+                                              extractor,
+                                              batch_size=config.batch_size,
+                                              max_clips=max_clips,
+                                              verbose=True)
+    else:
+        print(f"Extracting features from {len(videos)} video tensors...")
+        features = extractor.extract_features(videos,
+                                              batch_size=config.batch_size,
+                                              verbose=True)
+        features = features.numpy()
+
+    # Validate feature count
+    expected_count = config.num_videos * config.num_clips_per_video
+    if len(features) < expected_count:
+        raise ValueError(
+            f"ERROR: Only extracted {len(features)} features, but need {expected_count}!\n"
+            f"Found fewer videos than expected. Check your video directory.")
+    elif len(features) > expected_count:
+        print(f"Truncating {len(features)} features to {expected_count}")
+        features = features[:expected_count]
+
+    # Cache features if requested
+    if cache_path is not None:
+        script_dir = Path(__file__).parent
+        cache_dir = script_dir / cache_path
+        cache_dir.mkdir(parents=True, exist_ok=True)
+        cache_file = cache_dir / f"{config.extractor_model}_{cache_name}.pkl"
+        print(f"Caching features to {cache_file}")
+        with open(cache_file, 'wb') as f:
+            pickle.dump(features, f)
+
+    return features
+
+
+def compute_fvd_with_config(real_videos: str | Path | torch.Tensor,
+                            gen_videos: str | Path | torch.Tensor,
+                            config: FVDConfig,
+                            verbose: bool = True) -> dict:
+    """
+        Compute FVD using a standardized configuration.
+
+        This is the recommended way to compute FVD for reproducibility.
+
+        Args:
+            real_videos: Path or tensors
+            gen_videos: Path or tensors
+            config: FVDConfig specifying protocol
+            verbose: Print progress
+
+        Returns:
+            results: Dictionary with:
+                - 'fvd': FVD score (float)
+                - 'protocol': Protocol name (str)
+                - 'model': Feature extractor model name (str)
+                - 'config': Configuration dict
+
+        Example:
+            >>> config = FVDConfig.fvd2048_16f()
+            >>> results = compute_fvd_with_config('data/real/', 'outputs/gen/', config)
+            >>> print(f"FVD: {results['fvd']:.2f}")
+    """
+
+    # Seed for reproducibility
+    if config.seed is not None:
+        import random as _rnd
+        _rnd.seed(config.seed)
+        np.random.seed(config.seed)
+        torch.manual_seed(config.seed)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed_all(config.seed)
+
+    if verbose:
+        print("=" * 70)
+        print(f"Computing FVD with protocol: {config}")
+        print(f"Model: {config.extractor_model.upper()}")
+        print("=" * 70)
+        print("\nConfiguration:")
+        for key, value in config.to_dict().items():
+            print(f"  {key}: {value}")
+        print()
+
+    # Initialize Extractor using Factory
+    if verbose:
+        print(
+            f"\nInitializing {config.extractor_model.upper()} model on {config.device}..."
+        )
+
+    extractor = load_extractor(config.extractor_model, device=config.device)
+
+    # Extract features
+    if verbose:
+        print(f"\n{'='*70}")
+        print("Extracting REAL video features...")
+        print(f"{'='*70}")
+
+    real_features = load_or_compute_features(
+        videos=real_videos,
+        extractor=extractor,
+        config=config,
+        cache_path=config.cache_real_features,
+        cache_name="real_features")
+
+    if verbose:
+        print(f"\n{'='*70}")
+        print("Extracting GENERATED video features...")
+        print(f"{'='*70}")
+
+    gen_features = load_or_compute_features(videos=gen_videos,
+                                            extractor=extractor,
+                                            config=config,
+                                            cache_path=None,
+                                            cache_name="gen_features")
+
+    if verbose:
+        print(f"\nReal videos/clips: {len(real_features)}")
+        print(f"Generated videos/clips: {len(gen_features)}")
+        print(f"\n{'='*70}")
+        print("Computing statistics...")
+        print(f"{'='*70}")
+
+    mu_real, sigma_real = compute_statistics(real_features)
+    mu_gen, sigma_gen = compute_statistics(gen_features)
+
+    if verbose:
+        print(f"\n{'='*70}")
+        print("Computing Fréchet distance...")
+        print(f"{'='*70}")
+
+    fvd = compute_frechet_distance(mu_real, sigma_real, mu_gen, sigma_gen)
+
+    if verbose:
+        print(f"\n{'='*70}")
+        print(f"FVD Score ({config.extractor_model.upper()}): {fvd:.4f}")
+        print(f"Protocol: {config}")
+        print(f"{'='*70}\n")
+
+    results = {
+        'fvd': fvd,
+        'protocol': str(config),
+        'model': config.extractor_model,
+        'config': config.to_dict(),
+    }
+
+    return results
+
+
+def compute_fvd(real_videos: str | Path | torch.Tensor,
+                gen_videos: str | Path | torch.Tensor,
+                num_frames: int = 16,
+                batch_size: int = 32,
+                device: str = 'cuda',
+                num_videos: int | None = 2048,
+                cache_real_features: str | None = None,
+                i3d_model_path: str | None = None,
+                seed: int | None = None,
+                verbose: bool = True) -> float:
+    """
+    Backward compatibility wrapper for computing FVD (defaults to I3D).
+    """
+    num_videos = num_videos if num_videos is not None else 2048
+
+    config = FVDConfig(
+        num_videos=num_videos,
+        num_frames_per_clip=num_frames,
+        extractor_model='i3d',  # Default to I3D
+        batch_size=batch_size,
+        device=device,
+        cache_real_features=cache_real_features,
+        i3d_model_path=i3d_model_path,
+        seed=seed,
+    )
+
+    result = compute_fvd_with_config(real_videos, gen_videos, config, verbose)
+    return result['fvd']

benchmarks/fvd/i3d_model.py

@@ -0,0 +1,142 @@
+"""I3D Feature Extractor for FVD Computation"""
+
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from pathlib import Path
+from huggingface_hub import hf_hub_download
+from tqdm import tqdm
+from contextlib import suppress
+
+
+class I3DFeatureExtractor(nn.Module):
+    """
+    I3D feature extractor for FVD computation.
+    Extracts 400-dimensional features from videos using I3D model
+    trained on Kinetics-400.
+    """
+
+    REPO_ID = 'flateon/FVD-I3D-torchscript'
+    MODEL_FILENAME = 'i3d_torchscript.pt'
+
+    def __init__(self,
+                 device: str = 'cuda',
+                 cache_dir: str | Path | None = None):
+        super().__init__()
+
+        self.device_str = device
+        if device == 'cuda' and not torch.cuda.is_available():
+            print(
+                "Warning: CUDA requested but not available – falling back to CPU"
+            )
+            self.device = torch.device('cpu')
+        else:
+            self.device = torch.device(device)
+
+        self.cache_dir: str | None
+        if cache_dir is not None:
+            self.cache_dir = str(Path(cache_dir).resolve())
+        else:
+            self.cache_dir = None  # Use HF default cache
+
+        self.model = self._load_model()
+        self.model.eval()
+
+        with suppress(Exception):
+            self.model.to(self.device)
+
+    def _load_model(self) -> torch.nn.Module:
+        """Download and load I3D TorchScript model from Hugging Face Hub."""
+        print(f"Loading I3D model from Hugging Face Hub ({self.REPO_ID})...")
+
+        try:
+            # Download model from Hugging Face Hub
+            model_path = hf_hub_download(repo_id=self.REPO_ID,
+                                         filename=self.MODEL_FILENAME,
+                                         cache_dir=self.cache_dir)
+
+            # Load directly to chosen device
+            model = torch.jit.load(model_path, map_location=self.device)
+            print("I3D model loaded successfully")
+            return model
+
+        except Exception as e:
+            raise RuntimeError(
+                f"Failed to load I3D model from Hugging Face Hub. Error: {e}\n"
+                f"Ensure you have internet connection and huggingface_hub installed:\n"
+                f"pip install huggingface_hub") from e
+
+    def preprocess(self, videos: torch.Tensor) -> torch.Tensor:
+        """
+        Preprocess videos for I3D.
+        
+        Args:
+            videos: [B, T, C, H, W], values in [0, 255]
+        
+        Returns:
+            Preprocessed videos [B, C, T, 224, 224] (normalized and resized)
+        """
+        B, T, C, H, W = videos.shape
+
+        if T < 10:
+            raise ValueError(f"I3D requires at least 10 frames, got {T}")
+
+        # Normalize to [0, 1] if needed
+        if videos.max() > 1.0:
+            videos = videos / 255.0
+
+        # Resize to 224x224 if needed
+        if H != 224 or W != 224:
+            videos = videos.reshape(B * T, C, H, W)
+            videos = F.interpolate(videos,
+                                   size=(224, 224),
+                                   mode='bilinear',
+                                   align_corners=False)
+            videos = videos.reshape(B, T, C, 224, 224)
+
+        # Convert to [B, C, T, H, W] format
+        videos = videos.permute(0, 2, 1, 3, 4).contiguous()
+
+        return videos
+
+    @torch.no_grad()
+    def extract_features(self,
+                         videos: torch.Tensor,
+                         batch_size: int = 32,
+                         verbose: bool = True) -> torch.Tensor:
+        """
+        Extract I3D features
+        
+        Args:
+            videos: [N, T, C, H, W], values in [0, 255]
+            batch_size: Batch size for processing
+            verbose: Show progress bar
+        
+        Returns:
+            Features [N, 400]
+        """
+        N = len(videos)
+        all_features = []
+
+        iterator = range(0, N, batch_size)
+        if verbose:
+            iterator = tqdm(iterator, desc="Extracting I3D features")
+
+        for i in iterator:
+            batch = videos[i:i + batch_size].to(self.device)
+            batch = self.preprocess(batch)  # Now returns [B, C, T, H, W]
+
+            # Use the HF model without rescale/resize (we handle it in preprocess)
+            features = self.model(batch,
+                                  rescale=False,
+                                  resize=False,
+                                  return_features=True)
+
+            all_features.append(features.cpu())
+
+        return torch.cat(all_features, dim=0)
+
+    def __call__(self,
+                 videos: torch.Tensor,
+                 batch_size: int = 32) -> torch.Tensor:
+        return self.extract_features(videos, batch_size=batch_size)

benchmarks/fvd/run_fvd.py

@@ -0,0 +1,54 @@
+import sys
+from pathlib import Path
+
+root_dir = Path(__file__).parent.parent.parent
+sys.path.insert(0, str(root_dir))
+
+from benchmarks.fvd.fvd import FVDConfig, compute_fvd_with_config  # noqa: E402
+
+
+def main() -> None:
+    script_dir = Path(__file__).parent.resolve()
+
+    # Define directories
+    real_dir = "benchmarks/data/real_videos"
+    gen_dir = "benchmarks/data/generated_videos"
+
+    # Compare all 3 models
+    models_to_test = ['i3d', 'clip', 'videomae']
+
+    print(f"\n{'='*60}")
+    print("STARTING COMPARISON BENCHMARK")
+    print(f"{'='*60}")
+
+    for model_name in models_to_test:
+        print(f"\n>>> Running evaluation with {model_name.upper()}...")
+
+        try:
+            cfg = FVDConfig(
+                num_videos=650,
+                num_frames_per_clip=16,
+                extractor_model=model_name,
+                clip_strategy='beginning',
+                device='cuda',
+                seed=42,
+                # Use separate cache folders for each model to avoid conflicts
+                cache_real_features=str(script_dir / f'fvd-cache/{model_name}'),
+            )
+
+            results = compute_fvd_with_config(real_dir,
+                                              gen_dir,
+                                              cfg,
+                                              verbose=False)
+            print(f"FVD: {results['fvd']}\nModel: {results['model']}")
+
+        except Exception as e:
+            print(f"{model_name.upper()} Failed: {e}")
+
+    print(f"\n{'='*60}")
+    print("BENCHMARK COMPLETE")
+    print(f"{'='*60}")
+
+
+if __name__ == '__main__':
+    main()

benchmarks/fvd/validate_fvd.py

@@ -0,0 +1,97 @@
+#!/usr/bin/env python3
+import sys
+from pathlib import Path
+import shutil
+import random
+from fvd import compute_fvd_with_config, FVDConfig
+
+script_path = Path(__file__).resolve()
+fastvideo_root = script_path.parent.parent.parent
+sys.path.insert(0, str(fastvideo_root))
+
+
+def split_videos(video_dir: Path, n_per_subset: int = 128, seed: int = 42):
+    subset_a = video_dir.parent / 'bair_full_subset_A'
+    subset_b = video_dir.parent / 'bair_full_subset_B'
+
+    if subset_a.exists():
+        shutil.rmtree(subset_a)
+    if subset_b.exists():
+        shutil.rmtree(subset_b)
+
+    subset_a.mkdir(parents=True)
+    subset_b.mkdir(parents=True)
+
+    videos = sorted(video_dir.glob('*.mp4'))
+
+    random.seed(seed)
+    shuffled = list(videos)
+    random.shuffle(shuffled)
+
+    needed = n_per_subset * 2
+    if len(shuffled) > needed:
+        shuffled = shuffled[:needed]
+
+    mid = len(shuffled) // 2
+
+    print(f"\nSplitting {len(shuffled)} BAIR FULL videos:")
+    print(f"  Subset A: {mid} videos")
+    print(f"  Subset B: {len(shuffled) - mid} videos")
+
+    for v in shuffled[:mid]:
+        shutil.copy2(v, subset_a / v.name)
+
+    for v in shuffled[mid:]:
+        shutil.copy2(v, subset_b / v.name)
+
+    return subset_a, subset_b, mid
+
+
+def validate_fvd(subset_a: Path, subset_b: Path, num_videos: int):
+    config = FVDConfig(num_videos=num_videos,
+                       num_frames_per_clip=16,
+                       clip_strategy='beginning',
+                       batch_size=8,
+                       device='cuda',
+                       seed=42)
+
+    print("\n" + "=" * 70)
+    print("TEST 1: Identity Test")
+    print("=" * 70)
+
+    result1 = compute_fvd_with_config(real_videos=str(subset_a),
+                                      gen_videos=str(subset_a),
+                                      config=config,
+                                      verbose=False)
+    fvd_identity = result1['fvd']
+    print(f"\nIdentity FVD: {fvd_identity:.2f}")
+
+    print("\n" + "=" * 70)
+    print("TEST 2: Real vs Real")
+    print("=" * 70)
+
+    result2 = compute_fvd_with_config(real_videos=str(subset_a),
+                                      gen_videos=str(subset_b),
+                                      config=config,
+                                      verbose=False)
+    fvd_real = result2['fvd']
+    print(f"\nReal vs Real FVD: {fvd_real:.2f}")
+
+    print("\n" + "=" * 70)
+    print("RESULTS")
+    print("=" * 70)
+    print(f"Identity:        {fvd_identity:.2f}")
+    print(f"Real vs Real:    {fvd_real:.2f}")
+
+
+def main() -> None:
+    bair_dir = Path('benchmarks/data/bair_full_videos')
+
+    subset_a, subset_b, count = split_videos(bair_dir,
+                                             n_per_subset=128,
+                                             seed=42)
+    validate_fvd(subset_a, subset_b, count)
+
+
+if __name__ == '__main__':
+    main()

benchmarks/fvd/video_utils.py

@@ -0,0 +1,490 @@
+import torch
+import cv2
+import numpy as np
+from pathlib import Path
+from collections.abc import Iterator
+from tqdm import tqdm
+from enum import Enum
+
+
+class ClipSamplingStrategy(Enum):
+    """Clip sampling strategies for FVD evaluation."""
+    BEGINNING = 'beginning'  # Take first N frames (most common)
+    RANDOM = 'random'  # Random N consecutive frames
+    UNIFORM = 'uniform'  # Uniformly spaced frames across video
+    MIDDLE = 'middle'  # Middle N frames
+    SLIDING = 'sliding'  # Multiple sliding windows
+    ALL = 'all'  # All possible clips
+
+
+def _load_video_cv2(video_path: str | Path,
+                    num_frames: int | None = 16,
+                    sample_strategy: str = 'uniform') -> torch.Tensor:
+    """
+    Load video from video file using OpenCV.
+    
+    Args:
+        video_path: Path to video file (MP4, AVI, MOV, MKV)
+        num_frames: Number of frames to extract
+        sample_strategy: 'uniform' or 'random'
+    
+    Returns:
+        video: [T, C, H, W]
+    """
+    video_path = str(video_path)
+    cap = cv2.VideoCapture(video_path)
+
+    if not cap.isOpened():
+        raise RuntimeError(f"Cannot open video: {video_path}")
+
+    frames = []
+    total_frames = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
+
+    if num_frames is None:
+        # Read all available frames
+        while True:
+            ret, frame = cap.read()
+            if not ret:
+                break
+            frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
+            frames.append(frame)
+
+        cap.release()
+        if len(frames) == 0:
+            raise RuntimeError(f"Video has 0 frames: {video_path}")
+
+        frames = np.stack(frames)  # [T, H, W, C]
+        frames = torch.from_numpy(frames).permute(0, 3, 1,
+                                                  2).float()  # [T, C, H, W]
+        return frames
+
+    if total_frames == 0:
+        raise RuntimeError(f"Video has 0 frames: {video_path}")
+
+    # Determine frame indices for sampling
+    if total_frames < num_frames:
+        frame_indices = list(range(
+            total_frames)) + [total_frames - 1] * (num_frames - total_frames)
+    elif sample_strategy == 'uniform':
+        frame_indices = np.linspace(0, total_frames - 1, num_frames,
+                                    dtype=int).tolist()
+    elif sample_strategy == 'random':
+        frame_indices = sorted(
+            np.random.choice(total_frames, num_frames, replace=False))
+    else:
+        raise ValueError(f"Unknown sample_strategy: {sample_strategy}")
+
+    # Extract frames
+    for idx in frame_indices:
+        cap.set(cv2.CAP_PROP_POS_FRAMES, idx)
+        ret, frame = cap.read()
+
+        if not ret:
+            if len(frames) > 0:
+                frames.append(frames[-1].copy())
+            else:
+                h = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
+                w = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
+                frames.append(np.zeros((h, w, 3), dtype=np.uint8))
+            continue
+
+        frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
+        frames.append(frame)
+
+    cap.release()
+
+    frames = np.stack(frames)  # [T, H, W, C]
+    frames = torch.from_numpy(frames).permute(0, 3, 1,
+                                              2).float()  # [T, C, H, W]
+
+    return frames
+
+
+def _load_video_from_frames(
+        frame_dir: str | Path,
+        num_frames: int | None = 16,
+        sample_strategy: str = 'uniform',
+        frame_extensions: list[str] | None = None) -> torch.Tensor:
+    """
+    Load video from directory of frame images.
+    
+    Args:
+        frame_dir: Directory containing frames
+        num_frames: Number of frames to sample
+        sample_strategy: 'uniform' or 'random'
+        frame_extensions: Image file extensions to look for
+    
+    Returns:
+        video: [T, C, H, W]
+    """
+    if frame_extensions is None:
+        frame_extensions = ['.jpg', '.png', '.jpeg', '.bmp']
+
+    frame_dir = Path(frame_dir)
+
+    if not frame_dir.exists():
+        raise FileNotFoundError(f"Frame directory not found: {frame_dir}")
+
+    # Find all frames
+    frame_files: list[Path] = []
+    for ext in frame_extensions:
+        frame_files.extend(frame_dir.glob(f"*{ext}"))
+
+    if len(frame_files) == 0:
+        raise ValueError(
+            f"No frames found in {frame_dir} with extensions {frame_extensions}"
+        )
+
+    frame_files = sorted(frame_files, key=lambda x: x.name)
+    total_frames = len(frame_files)
+
+    # Determine frame indices
+    if num_frames is None:
+        frame_indices = list(range(total_frames))
+    else:
+        if total_frames < num_frames:
+            frame_indices = list(range(total_frames)) + [total_frames - 1] * (
+                num_frames - total_frames)
+        elif sample_strategy == 'uniform':
+            frame_indices = np.linspace(0,
+                                        total_frames - 1,
+                                        num_frames,
+                                        dtype=int).tolist()
+        elif sample_strategy == 'random':
+            frame_indices = sorted(
+                np.random.choice(total_frames, num_frames, replace=False))
+        else:
+            raise ValueError(f"Unknown sample_strategy: {sample_strategy}")
+
+    # Load frames
+    frames = []
+    for idx in frame_indices:
+        frame_path = frame_files[idx]
+        frame = cv2.imread(str(frame_path))
+
+        if frame is None:
+            raise RuntimeError(f"Failed to load frame: {frame_path}")
+
+        frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
+        frames.append(frame)
+
+    # Stack and convert to tensor
+    frames = np.stack(frames)  # [T, H, W, C]
+    frames = torch.from_numpy(frames).permute(0, 3, 1,
+                                              2).float()  # [T, C, H, W]
+
+    return frames
+
+
+def _detect_video_format(path: str | Path) -> str:
+    """
+    Detect if path is a video file or frame directory.
+    
+    Returns:
+        'video_file', 'frame_directory', or 'unknown'
+    """
+    path = Path(path)
+
+    if path.is_file():
+        return 'video_file'
+    elif path.is_dir():
+        # Check if contains image files
+        image_extensions = ['.jpg', '.jpeg', '.png', '.bmp']
+        for ext in image_extensions:
+            if list(path.glob(f"*{ext}")):
+                return 'frame_directory'
+        return 'unknown'
+    else:
+        raise ValueError(f"Path does not exist: {path}")
+
+
+def load_video_auto(video_path: str | Path,
+                    num_frames: int | None = 16,
+                    sample_strategy: str = 'uniform') -> torch.Tensor:
+    """
+    Automatically detect format and load video.
+    
+    Supports:
+    - Video files (MP4, AVI, MOV, MKV)
+    - Frame directories (JPG, PNG)
+    
+    Args:
+        video_path: Path to video file or frame directory
+        num_frames: Number of frames to extract
+        sample_strategy: 'uniform' or 'random'
+    
+    Returns:
+        video: [T, C, H, W]
+    """
+    format_type = _detect_video_format(video_path)
+
+    if format_type == 'video_file':
+        return _load_video_cv2(video_path, num_frames, sample_strategy)
+    elif format_type == 'frame_directory':
+        return _load_video_from_frames(video_path, num_frames, sample_strategy)
+    else:
+        raise ValueError(f"Unknown video format at {video_path}")
+
+
+def sample_clips_from_video(
+        video: torch.Tensor,
+        num_frames_per_clip: int = 16,
+        num_clips: int = 1,
+        strategy: str | ClipSamplingStrategy = ClipSamplingStrategy.BEGINNING,
+        frame_stride: int = 1,
+        temporal_stride: int = 1) -> list[torch.Tensor]:
+    """
+    Sample clips from a video with various strategies.
+        
+    Args:
+        video: [T, C, H, W] full video
+        num_frames_per_clip: Frames per clip
+        num_clips: Number of clips to extract
+        strategy: ClipSamplingStrategy or string ('beginning', 'random', etc.)
+        frame_stride: Skip frames (FPS control: 1=all, 2=every 2nd, 8=every 8th)
+        temporal_stride: Stride between clips for sliding window
+    
+    Returns:
+        List of clips, each [num_frames_per_clip, C, H, W]
+    
+    Examples:
+        >>> # Beginning clip (most common for FVD)
+        >>> clips = sample_clips_from_video(video, 16, strategy='beginning')
+        
+        >>> # Multiple random clips
+        >>> clips = sample_clips_from_video(video, 16, num_clips=4, strategy='random')
+        
+        >>> # Subsample FPS by 2x (every 2nd frame)
+        >>> clips = sample_clips_from_video(video, 16, frame_stride=2)
+        
+        >>> # Sliding window with overlap
+        >>> clips = sample_clips_from_video(video, 16, strategy='sliding', temporal_stride=8)
+    """
+    # Convert string to enum if needed
+    if isinstance(strategy, str):
+        strategy = ClipSamplingStrategy(strategy)
+
+    T, C, H, W = video.shape
+
+    # Apply frame stride (FPS subsampling)
+    if frame_stride > 1:
+        video = video[::frame_stride]
+        T = len(video)
+
+    effective_clip_length = num_frames_per_clip
+
+    # Handle videos shorter than clip length
+    if effective_clip_length > T:
+        pad_length = effective_clip_length - T
+        last_frame = video[-1:].repeat(pad_length, 1, 1, 1)
+        video = torch.cat([video, last_frame], dim=0)
+        T = len(video)
+
+    clips = []
+
+    if strategy == ClipSamplingStrategy.BEGINNING:
+        # Take first clip (most common for FVD evaluation)
+        clip = video[:effective_clip_length]
+        clips.append(clip)
+
+    elif strategy == ClipSamplingStrategy.MIDDLE:
+        # Take middle clip
+        start = (T - effective_clip_length) // 2
+        clip = video[start:start + effective_clip_length]
+        clips.append(clip)
+
+    elif strategy == ClipSamplingStrategy.RANDOM:
+        # Sample N random clips
+        for _ in range(num_clips):
+            if effective_clip_length == T:
+                start = 0
+            else:
+                start = np.random.randint(0, T - effective_clip_length + 1)
+            clip = video[start:start + effective_clip_length]
+            clips.append(clip)
+
+    elif strategy == ClipSamplingStrategy.UNIFORM:
+        # Uniformly spaced clips
+        if num_clips == 1:
+            # Single clip from middle
+            start = (T - effective_clip_length) // 2
+            clip = video[start:start + effective_clip_length]
+            clips.append(clip)
+        else:
+            # Multiple uniformly spaced clips
+            step = (T - effective_clip_length) / (num_clips -
+                                                  1) if num_clips > 1 else 0
+            for i in range(num_clips):
+                start = int(i * step)
+                start = min(start, T - effective_clip_length)
+                clip = video[start:start + effective_clip_length]
+                clips.append(clip)
+
+    elif strategy == ClipSamplingStrategy.SLIDING:
+        # Sliding window with stride
+        for start in range(0, T - effective_clip_length + 1, temporal_stride):
+            clip = video[start:start + effective_clip_length]
+            clips.append(clip)
+            if len(clips) >= num_clips:
+                break
+
+    elif strategy == ClipSamplingStrategy.ALL:
+        # All possible clips (overlapping)
+        for start in range(T - effective_clip_length + 1):
+            clip = video[start:start + effective_clip_length]
+            clips.append(clip)
+
+    else:
+        raise ValueError(f"Unknown strategy: {strategy}")
+
+    return clips
+
+
+def load_video_clips_streaming(directory: str | Path,
+                               num_frames: int = 16,
+                               max_videos: int | None = None,
+                               clip_strategy: str
+                               | ClipSamplingStrategy = 'beginning',
+                               frame_stride: int = 1,
+                               num_clips_per_video: int = 1,
+                               video_extensions: list[str] | None = None,
+                               support_frame_dirs: bool = True,
+                               target_size: tuple[int, int] | None = (224, 224),
+                               verbose: bool = True) -> Iterator[torch.Tensor]:
+    """
+    This generator yields clips one-by-one instead of loading all videos into RAM.
+    Perfect for large datasets where memory is limited.
+    
+    Args:
+        directory: Path to directory with videos
+        num_frames: Frames per clip
+        max_videos: Max videos to load
+        clip_strategy: 'beginning', 'random', 'uniform', etc.
+        frame_stride: Frame skip (1=all, 2=every 2nd, 8=every 8th)
+        num_clips_per_video: Number of clips per video
+        video_extensions: Video file extensions
+        support_frame_dirs: Also load frame directories
+        target_size: Resize clips to (H, W). If None, keep original size.
+        verbose: Show progress
+    
+    Yields:
+        clip: [T, C, H, W] individual clips
+    
+    Example:
+        >>> for clip in load_video_clips_streaming('data/videos/', num_frames=16):
+        >>>     features = model.extract_features(clip.unsqueeze(0))
+        >>>     # Process one clip at a time - low memory usage!
+    """
+    if video_extensions is None:
+        video_extensions = ['.mp4', '.avi', '.mov', '.mkv']
+
+    directory = Path(directory)
+
+    if not directory.exists():
+        raise FileNotFoundError(f"Directory not found: {directory}")
+
+    # Find video paths
+    video_paths: list[Path] = []
+
+    # Find video files
+    for ext in video_extensions:
+        video_paths.extend(directory.glob(f"**/*{ext}"))
+
+    # Find frame directories if enabled
+    if support_frame_dirs:
+        for subdir in directory.iterdir():
+            if subdir.is_dir():
+                # Check if it contains frames
+                image_extensions = ['.jpg', '.jpeg', '.png', '.bmp']
+                for ext in image_extensions:
+                    if list(subdir.glob(f"*{ext}")):
+                        video_paths.append(subdir)
+                        break
+
+    if len(video_paths) == 0:
+        raise ValueError(f"No videos found in {directory}")
+
+    video_paths = sorted(video_paths)
+
+    if max_videos is not None:
+        video_paths = video_paths[:max_videos]
+
+    if verbose:
+        print(f"Found {len(video_paths)} videos in {directory}")
+        if num_clips_per_video > 1:
+            print(f"Extracting {num_clips_per_video} clips per video...")
+        if frame_stride > 1:
+            print(f"Subsampling frames with stride {frame_stride}...")
+        if target_size:
+            print(f"Resizing clips to {target_size}...")
+
+    # Track statistics
+    failed_count = 0
+    total_clips = 0
+
+    iterator = tqdm(video_paths,
+                    desc="Loading videos") if verbose else video_paths
+
+    for video_path in iterator:
+        try:
+            # Load full video
+            video = load_video_auto(video_path,
+                                    num_frames=None,
+                                    sample_strategy='uniform')
+
+            # Sample clips from video
+            clips = sample_clips_from_video(video,
+                                            num_frames_per_clip=num_frames,
+                                            num_clips=num_clips_per_video,
+                                            strategy=clip_strategy,
+                                            frame_stride=frame_stride)
+
+            if target_size is not None:
+                resized_clips = []
+                for clip in clips:
+                    T, C, H, W = clip.shape
+                    if target_size != (H, W):
+                        # Resize to target size
+                        clip = clip.contiguous(
+                        )  # Fix non-contiguous tensors first
+                        clip_flat = clip.view(T * C, H,
+                                              W).unsqueeze(0)  # [1, T*C, H, W]
+                        clip_resized = torch.nn.functional.interpolate(
+                            clip_flat,
+                            size=target_size,
+                            mode='bilinear',
+                            align_corners=False)
+                        clip = clip_resized.squeeze(0).view(
+                            T, C, target_size[0],
+                            target_size[1])  # Back to [T, C, H, W]
+                    resized_clips.append(clip)
+                clips = resized_clips
+
+            # Yield clips one by one
+            for clip in clips:
+                yield clip
+                total_clips += 1
+
+            # Free memory
+            del video, clips
+
+        except Exception as e:
+            failed_count += 1
+            if verbose:
+                print(f"\nWarning: Failed to load {video_path}: {e}")
+            continue
+
+    # Validate
+    if total_clips == 0:
+        raise RuntimeError(f"Failed to load any videos from {directory}")
+
+    failure_rate = failed_count / len(video_paths)
+    if failure_rate > 0.1:  # More than 10% failed
+        print(
+            f"\nWARNING: {failure_rate:.1%} of videos failed to load ({failed_count}/{len(video_paths)})"
+        )
+
+    if verbose:
+        print(
+            f"\nSuccessfully loaded {total_clips} clips from {len(video_paths) - failed_count} videos"
+        )

benchmarks/scripts/run.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+# 1. Install missing dependency
+pip install -q opencv-python-headless transformers huggingface_hub
+
+# 2. Run FVD script
+python benchmarks/fvd/run_fvd.py

benchmarks/scripts/setup_fvd.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+# 1. Install missing dependency
+pip install -q opencv-python-headless

comfyui/assets/icon_simple.svg

@@ -0,0 +1,6 @@
+<svg width="160" height="93" viewBox="0 0 160 93" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M28.8511 91.66L57.6319 1.86368H64.5394L35.7585 91.66H28.8511Z" fill="#356CFF" stroke="#356CFF" stroke-width="2.30244"/>
+<path d="M15.0376 91.66L43.8185 1.86368H46.1209L17.3401 91.66H15.0376Z" fill="#356CFF" stroke="#356CFF" stroke-width="2.30244"/>
+<path d="M1.22217 91.66L30.003 1.86366H31.1543L2.3734 91.66H1.22217Z" fill="#356CFF" stroke="#356CFF" stroke-width="1.15122"/>
+<path d="M71.4465 1.86483L42.666 91.6599H69.144L78.3538 58.2746H123.251L129.007 39.855H84.1099L89.866 22.5868H152.032L157.788 1.86483H71.4465Z" fill="#356CFF" stroke="#356CFF" stroke-width="2.30244"/>
+</svg>

csrc/attn/MANIFEST.in

@@ -1,2 +0,0 @@
-recursive-include tk *
-include config.py

csrc/attn/README.md

@@ -1,93 +0,0 @@
-
-
-# Attention Kernel Used in FastVideo
-
-## Sliding Tile Attention (STA)
-We only support H100 for STA.
-```bash
-git submodule update --init --recursive
-python setup_sta.py install
-```
-
-## Video Sparse Attention (VSA)
-We support H100 (via TK) and RTX 4090 (via triton) for VSA.
-```bash
-git submodule update --init --recursive
-python setup_vsa.py install
-```
-
-If you encounter error during installation, try below:
-Install C++20 for ThunderKittens:
-```bash
-sudo apt update
-sudo apt install gcc-11 g++-11
-
-sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
-
-sudo apt update
-sudo apt install clang-11
-```
-(If you use CUDA12.4)
-```bash
-export CUDA_HOME=/usr/local/cuda-12.4
-export PATH=${CUDA_HOME}/bin:${PATH} 
-export LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
-```
-
-
-
-## Usage
-### STA
-End-2-end inference with FastVideo:
-```bash
-bash scripts/inference/v1_inference_wan_STA.sh
-```
-
-If you want to use sliding tile attention in your custom model:
-```python
-from st_attn import sliding_tile_attention
-# assuming video size (T, H, W) = (30, 48, 80), text tokens = 256 with padding. 
-# q, k, v: [batch_size, num_heads, seq_length, head_dim], seq_length = T*H*W + 256
-# a tile is a cube of size (6, 8, 8)
-# window_size in tiles: [(window_t, window_h, window_w), (..)...]. For example, window size (3, 3, 3) means a query can attend to (3x6, 3x8, 3x8) = (18, 24, 24) tokens out of the total 30x48x80 video.
-# text_length: int ranging from 0 to 256
-# If your attention contains text token (Hunyuan)
-out = sliding_tile_attention(q, k, v, window_size, text_length)
-# If your attention does not contain text token (StepVideo)
-out = sliding_tile_attention(q, k, v, window_size, 0, False)
-```
-
-### VSA
-We do not officially supoort end-2-end inference with VSA in FastVideo yet. Stay tuned.
-
-
-## Test
-```bash
-python tests/test_sta.py # test STA
-python tests/test_block_sparse.py # test VSA
-```
-## Benchmark
-```bash
-python benchmarks/bench_sta.py
-```
-
-
-## How Does STA Work?
-We give a demo for 2D STA with window size (6,6) operating on a (10, 10) image. 
-
-
-https://github.com/user-attachments/assets/f3b6dd79-7b43-4b60-a0fa-3d6495ec5747
-
-## Why is STA Fast?
-2D/3D Sliding Window Attention (SWA) creates many mixed blocks in the attention map. Even though mixed blocks have less output value,a mixed block is significantly slower than a dense block due to the GPU-unfriendly masking operation. 
-
-STA removes mixed blocks.
-
-
-<div align="center">
-<img src=../../assets/sliding_tile_attn_map.png width="80%"/>
-</div>
-
-## Acknowledgement
-
-We learned or reuse code from FlexAtteniton, NATEN, and ThunderKittens.

csrc/attn/benchmarks/bench_sta.py

@@ -1,147 +0,0 @@
-import os
-from collections import defaultdict
-
-import matplotlib.pyplot as plt
-import numpy as np
-import torch
-from st_attn import sliding_tile_attention
-from triton.testing import do_bench
-
-
-def flops(batch, seqlen, nheads, headdim, causal, mode="fwd"):
-    assert mode in ["fwd", "bwd", "fwd_bwd"]
-    f = 4 * batch * seqlen**2 * nheads * headdim // (2 if causal else 1)
-    return f if mode == "fwd" else (2.5 * f if mode == "bwd" else 3.5 * f)
-
-
-def compute_TFLOPS(flops, ms):
-    flops = flops / 1e12
-    ms = ms / 1e3
-    return flops / ms
-
-
-def benchmark_attention(configurations):
-    results = {'fwd': defaultdict(list), 'bwd': defaultdict(list)}
-
-    for B, H, N, D, causal, dit_seq_shape, window_size in configurations:
-        print("=" * 60)
-        print(f"Timing forward and backward pass for B={B}, H={H}, N={N}, D={D}, causal={causal}")
-
-        q = torch.randn(B, H, N, D, dtype=torch.bfloat16, device='cuda', requires_grad=False).contiguous()
-        k = torch.randn(B, H, N, D, dtype=torch.bfloat16, device='cuda', requires_grad=False).contiguous()
-        v = torch.randn(B, H, N, D, dtype=torch.bfloat16, device='cuda', requires_grad=False).contiguous()
-
-        # grad_output = torch.randn_like(q, requires_grad=False).contiguous()
-        # qg = torch.zeros_like(q, requires_grad=False, dtype=torch.float).contiguous()
-        # kg = torch.zeros_like(k, requires_grad=False, dtype=torch.float).contiguous()
-        # vg = torch.zeros_like(v, requires_grad=False, dtype=torch.float).contiguous()
-
-
-        # # Warmup for forward pass
-        # for _ in range(10):
-        #     o = sliding_tile_attention(q, k, v, [[3, 6, 10]] * 24, 0, False, dit_seq_shape)
-
-        # # Time the forward pass
-        # for i in range(10):
-        #     start_events_fwd[i].record()
-        #     o = sliding_tile_attention(q, k, v, [[3, 6, 10]] * 24, 0, False, dit_seq_shape)
-        #     end_events_fwd[i].record()
-        ms = do_bench(lambda: sliding_tile_attention(q, k, v, [window_size] * 24, 0, False, dit_seq_shape))
-
-        # times_fwd = [s.elapsed_time(e) for s, e in zip(start_events_fwd, end_events_fwd)]
-        # time_us_fwd = np.mean(times_fwd) * 1000
-
-        tflops_fwd = compute_TFLOPS(flops(B, N, H, D, causal, 'fwd'), ms)
-        results['fwd'][(D, causal)].append((N, tflops_fwd))
-
-        print(f"Average time for forward pass (ms): {ms:.2f}")
-        print(f"Average TFLOPS: {tflops_fwd}")
-        print("-" * 60)
-
-        # torch.cuda.empty_cache()
-        # torch.cuda.synchronize()
-
-        # # Prepare for timing backward pass
-        # start_events_bwd = [torch.cuda.Event(enable_timing=True) for _ in range(10)]
-        # end_events_bwd = [torch.cuda.Event(enable_timing=True) for _ in range(10)]
-
-        # # Warmup for backward pass
-        # for _ in range(10):
-        #     qg, kg, vg = tk.mha_backward(q, k, v, o, l_vec, grad_output, causal)
-
-        # # Time the backward pass
-        # for i in range(10):
-        #     start_events_bwd[i].record()
-        #     qg, kg, vg = tk.mha_backward(q, k, v, o, l_vec, grad_output, causal)
-        #     end_events_bwd[i].record()
-
-        # torch.cuda.synchronize()
-        # times_bwd = [s.elapsed_time(e) for s, e in zip(start_events_bwd, end_events_bwd)]
-        # time_us_bwd = np.mean(times_bwd) * 1000
-
-        # tflops_bwd = compute_TFLOPS(flops(B, N, H, D, causal, 'bwd'), ms)
-        # results['bwd'][(D, causal)].append((N, tflops_bwd))
-
-        # print(f"Average time for backward pass(ms): {ms:.2f}")
-        # print(f"Average TFLOPS: {tflops_bwd}")
-        # print("=" * 60)
-
-        torch.cuda.empty_cache()
-
-    return results
-
-
-def plot_results(results):
-    os.makedirs('benchmark_results', exist_ok=True)
-    for mode in ['fwd', 'bwd']:
-        for (D, causal), values in results[mode].items():
-            seq_lens = [x[0] for x in values]
-            tflops = [x[1] for x in values]
-
-            plt.figure(figsize=(10, 6))
-            bars = plt.bar(range(len(seq_lens)), tflops, tick_label=seq_lens)
-            plt.xlabel('Sequence Length')
-            plt.ylabel('TFLOPS')
-            plt.title(f'{mode.upper()} Pass - Head Dim: {D}, Causal: {causal}')
-            plt.grid(True)
-
-            # Adding the numerical y value on top of each bar
-            for bar in bars:
-                yval = bar.get_height()
-                plt.text(bar.get_x() + bar.get_width() / 2, yval, round(yval, 2), ha='center', va='bottom')
-
-            filename = f'benchmark_results/{mode}_D{D}_causal{causal}.png'
-            plt.savefig(filename)
-            plt.close()
-
-
-# Example list of configurations to test
-configurations = [
-    (2, 24, 69120, 128, False, '18x48x80', [3, 6, 10]),
-    (2, 24, 69120, 128, True, '18x48x80', [3, 6, 10]),
-    (2, 24, 82944, 128, False, '36x48x48', [3, 3, 6]), # Stepvideo
-    (2, 24, 82944, 128, True, '36x48x48', [3, 3, 6]),
-    # (16, 16, 768*16,  128, False),
-    # (16, 16, 768*2,  128, False),
-    # (16, 16, 768*4,  128, False),
-    # (16, 16, 768*8,  128, False),
-    # (16, 16, 768*16, 128, False),
-    # (16, 16, 768,    128, True),
-    # (16, 16, 768*2,  128, True),
-    # (16, 16, 768*4,  128, True),
-    # (16, 16, 768*8,  128, True),
-    # (16, 16, 768*16, 128, True),
-    # (16, 32, 768,    64,  False),
-    # (16, 32, 768*2,  64,  False),
-    # (16, 32, 768*4,  64,  False),
-    # (16, 32, 768*8,  64,  False),
-    # (16, 32, 768*16, 64,  False),
-    # (16, 32, 768,    64,  True),
-    # (16, 32, 768*2,  64,  True),
-    # (16, 32, 768*4,  64,  True),
-    # (16, 32, 768*8,  64,  True),
-    # (16, 32, 768*16, 64,  True),
-]
-
-results = benchmark_attention(configurations)
-# plot_results(results)

csrc/attn/benchmarks/bench_vsa_hopper.py

@@ -1,225 +0,0 @@
-import torch
-import argparse
-from flash_attn.utils.benchmark import benchmark_forward
-from vsa import block_sparse_fwd, block_sparse_bwd
-from vsa import BLOCK_M, BLOCK_N
-
-import numpy as np
-import random
-
-def set_seed(seed: int = 42):
-    # Python random module
-    random.seed(seed)
-
-    # NumPy
-    np.random.seed(seed)
-
-    # PyTorch
-    torch.manual_seed(seed)
-    torch.cuda.manual_seed(seed)
-    torch.cuda.manual_seed_all(seed)  # if using multi-GPU
-
-def parse_arguments():
-    parser = argparse.ArgumentParser(description='Benchmark Block Sparse Attention')
-    parser.add_argument('--batch_size', type=int, default=1, help='Batch size')
-    parser.add_argument('--num_heads', type=int, default=12, help='Number of heads')
-    parser.add_argument('--head_dim', type=int, default=64, help='Head dimension')
-    parser.add_argument('--topk', type=int, default=None, help='Number of kv blocks each q block attends to')
-    parser.add_argument('--seq_lengths', type=int, nargs='+', default=[49152], help='Sequence lengths to benchmark')
-    return parser.parse_args()
-
-def create_input_tensors(batch, head, seq_len, headdim):
-    """Create random input tensors for attention."""
-    q = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    k = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    v = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    return q, k, v
-
-def generate_block_sparse_pattern(bs, h, num_q_blocks, num_kv_blocks, k, device="cuda"):
-    """
-    Generate a block sparse pattern where each q block attends to exactly k kv blocks.
-    
-    Args:
-        bs: batch size
-        h: number of heads
-        num_q_blocks: number of query blocks
-        num_kv_blocks: number of key-value blocks
-        k: number of kv blocks each q block attends to
-        device: device to create tensors on
-        
-    Returns:
-        q2k_block_sparse_index: [bs, h, num_q_blocks, k]
-            Contains the indices of kv blocks that each q block attends to.
-        q2k_block_sparse_num: [bs, h, num_q_blocks]
-            Contains the number of kv blocks that each q block attends to (all equal to k).
-        k2q_block_sparse_index: [bs, h, num_kv_blocks, num_q_blocks]
-            Contains the indices of q blocks that attend to each kv block.
-        k2q_block_sparse_num: [bs, h, num_kv_blocks]
-            Contains the number of q blocks that attend to each kv block.
-        block_sparse_mask: [bs, h, num_q_blocks, num_kv_blocks]
-            Binary mask where 1 indicates attention connection.
-    """
-    # Ensure k is not larger than num_kv_blocks
-    k = min(k, num_kv_blocks)
-    
-    # Create random scores for sampling
-    scores = torch.rand(bs, h, num_q_blocks, num_kv_blocks, device=device)
-    
-    # Get top-k indices for each q block
-    _, q2k_block_sparse_index = torch.topk(scores, k, dim=-1)
-    q2k_block_sparse_index = q2k_block_sparse_index.to(torch.int32)
-    
-    # sort q2k_block_sparse_index
-    q2k_block_sparse_index, _ = torch.sort(q2k_block_sparse_index, dim=-1)
-
-    # All q blocks attend to exactly k kv blocks
-    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks), k, dtype=torch.int32, device=device)
-    
-    # Create the corresponding mask
-    block_sparse_mask = torch.zeros(bs, h, num_q_blocks, num_kv_blocks, dtype=torch.bool, device=device)
-    
-    # Fill in the mask based on the indices
-    for b in range(bs):
-        for head in range(h):
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx]
-                block_sparse_mask[b, head, q_idx, kv_indices] = True
-    
-    # Create the reverse mapping (k2q)
-    # First, initialize lists to collect q indices for each kv block
-    k2q_indices_list = [[[] for _ in range(num_kv_blocks)] for _ in range(bs * h)]
-    
-    # Populate the lists based on q2k mapping
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx].tolist()
-                for kv_idx in kv_indices:
-                    k2q_indices_list[flat_idx][kv_idx].append(q_idx)
-    
-    # Find the maximum number of q blocks that attend to any kv block
-    max_q_per_kv = 0
-    for flat_idx in range(bs * h):
-        for kv_idx in range(num_kv_blocks):
-            max_q_per_kv = max(max_q_per_kv, len(k2q_indices_list[flat_idx][kv_idx]))
-    
-    # Create tensors for k2q mapping
-    k2q_block_sparse_index = torch.full((bs, h, num_kv_blocks, max_q_per_kv), -1, 
-                                        dtype=torch.int32, device=device)
-    k2q_block_sparse_num = torch.zeros((bs, h, num_kv_blocks), 
-                                       dtype=torch.int32, device=device)
-    
-    # Fill the tensors
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for kv_idx in range(num_kv_blocks):
-                q_indices = k2q_indices_list[flat_idx][kv_idx]
-                num_q = len(q_indices)
-                k2q_block_sparse_num[b, head, kv_idx] = num_q
-                if num_q > 0:
-                    k2q_block_sparse_index[b, head, kv_idx, :num_q] = torch.tensor(
-                        q_indices, dtype=torch.int32, device=device)
-                
-    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask
-
-def benchmark_block_sparse_attention(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, flops):
-    """Benchmark block sparse attention forward and backward passes."""
-    print("\n=== BLOCK SPARSE ATTENTION BENCHMARK ===")
-    
-    # Forward pass
-    # Warm-up run
-    o, l_vec = block_sparse_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num)
-    torch.cuda.synchronize()
-    
-    # Benchmark forward
-    _, fwd_time = benchmark_forward(
-        block_sparse_fwd,
-        q, k, v, q2k_block_sparse_index, q2k_block_sparse_num,
-        repeats=20,
-        verbose=False,
-        desc='Block Sparse Forward'
-    )
-    
-    sparse_tflops = flops / fwd_time.mean * 1e-12
-    print(f"Block Sparse Forward - TFLOPS: {sparse_tflops:.2f}")
-    
-    # Backward pass
-    grad_output = torch.randn_like(o)
-    
-    # Warm-up runs
-    for _ in range(5):
-        block_sparse_bwd(q, k, v, o, l_vec, grad_output, k2q_block_sparse_index, k2q_block_sparse_num)
-    torch.cuda.synchronize()
-    
-    # Benchmark backward
-    _, bwd_time = benchmark_forward(
-        block_sparse_bwd,
-        q, k, v, o, l_vec, grad_output, k2q_block_sparse_index, k2q_block_sparse_num,
-        repeats=20,
-        verbose=False,
-        desc='Block Sparse Backward'
-    )
-    bwd_flops = 2.5 * flops  # Approximation
-
-    sparse_bwd_tflops = bwd_flops / bwd_time.mean * 1e-12
-    print(f"Block Sparse Backward - TFLOPS: {sparse_bwd_tflops:.2f}")
-    
-    return sparse_tflops, sparse_bwd_tflops
-
-def main():
-    args = parse_arguments()
-
-    set_seed(42)
-    
-    # Extract parameters
-    batch = args.batch_size
-    head = args.num_heads
-    headdim = args.head_dim
-    
-    print(f"Block Sparse Attention Benchmark")
-    print(f"batch: {batch}, head: {head}, headdim: {headdim}")
-    
-    # Test with different sequence lengths
-    for seq_len in args.seq_lengths:
-        # Skip very long sequences if they might cause OOM
-        if seq_len > 16384 and batch > 1:
-            continue
-            
-        print("="*100)
-        print(f"\nSequence length: {seq_len}")
-        
-        # Calculate theoretical FLOPs for attention
-        flops = 4 * batch * head * headdim * seq_len * seq_len
-        
-        # Create input tensors
-        q, k, v = create_input_tensors(batch, head, seq_len, headdim)
-        
-        # Setup block sparse parameters
-        num_q_blocks = seq_len // BLOCK_M
-        num_kv_blocks = seq_len // BLOCK_N
-        
-        # Determine k value (number of kv blocks per q block)
-        topk = args.topk
-        if topk is None:
-            topk = num_kv_blocks // 10  # Default to ~90% sparsity if k is not specified
-        topk = max(1, topk)       
-        print(f"Using topk={topk} kv blocks per q block (out of {num_kv_blocks} total kv blocks)")
-        
-        # Generate block sparse pattern
-        q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, _ = generate_block_sparse_pattern(
-            batch, head, num_q_blocks, num_kv_blocks, topk, device="cuda")
-        
-        # Benchmark block sparse attention
-        sparse_fwd, sparse_bwd = benchmark_block_sparse_attention(
-            q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, flops
-        )
-        
-        # Print results
-        print("\n=== PERFORMANCE RESULTS ===")
-        print(f"Block Sparse Forward - TFLOPS: {sparse_fwd:.2f}")
-        print(f"Block Sparse Backward - TFLOPS: {sparse_bwd:.2f}")
-
-if __name__ == "__main__":
-    main()

csrc/attn/benchmarks/bench_vsa_triton.py

@@ -1,217 +0,0 @@
-import torch
-import argparse
-import triton.testing
-from vsa import block_sparse_attn
-from vsa import BLOCK_M, BLOCK_N
-
-import numpy as np
-import random
-
-def set_seed(seed: int = 42):
-    # Python random module
-    random.seed(seed)
-
-    # NumPy
-    np.random.seed(seed)
-
-    # PyTorch
-    torch.manual_seed(seed)
-    torch.cuda.manual_seed(seed)
-    torch.cuda.manual_seed_all(seed)  # if using multi-GPU
-
-def parse_arguments():
-    parser = argparse.ArgumentParser(description='Benchmark Block Sparse Attention')
-    parser.add_argument('--batch_size', type=int, default=1, help='Batch size')
-    parser.add_argument('--num_heads', type=int, default=12, help='Number of heads')
-    parser.add_argument('--head_dim', type=int, default=64, help='Head dimension')
-    parser.add_argument('--topk', type=int, default=None, help='Number of kv blocks each q block attends to')
-    parser.add_argument('--seq_lengths', type=int, nargs='+', default=[49152], help='Sequence lengths to benchmark')
-    return parser.parse_args()
-
-def create_input_tensors(batch, head, seq_len, headdim):
-    """Create random input tensors for attention."""
-    q = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    k = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    v = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    return q, k, v
-
-def generate_block_sparse_pattern(bs, h, num_q_blocks, num_kv_blocks, k, device="cuda"):
-    """
-    Generate a block sparse pattern where each q block attends to exactly k kv blocks.
-    
-    Args:
-        bs: batch size
-        h: number of heads
-        num_q_blocks: number of query blocks
-        num_kv_blocks: number of key-value blocks
-        k: number of kv blocks each q block attends to
-        device: device to create tensors on
-        
-    Returns:
-        q2k_block_sparse_index: [bs, h, num_q_blocks, k]
-            Contains the indices of kv blocks that each q block attends to.
-        q2k_block_sparse_num: [bs, h, num_q_blocks]
-            Contains the number of kv blocks that each q block attends to (all equal to k).
-        k2q_block_sparse_index: [bs, h, num_kv_blocks, num_q_blocks]
-            Contains the indices of q blocks that attend to each kv block.
-        k2q_block_sparse_num: [bs, h, num_kv_blocks]
-            Contains the number of q blocks that attend to each kv block.
-        block_sparse_mask: [bs, h, num_q_blocks, num_kv_blocks]
-            Binary mask where 1 indicates attention connection.
-    """
-    # Ensure k is not larger than num_kv_blocks
-    k = min(k, num_kv_blocks)
-    
-    # Create random scores for sampling
-    scores = torch.rand(bs, h, num_q_blocks, num_kv_blocks, device=device)
-    
-    # Get top-k indices for each q block
-    _, q2k_block_sparse_index = torch.topk(scores, k, dim=-1)
-    q2k_block_sparse_index = q2k_block_sparse_index.to(torch.int32)
-    
-    # sort q2k_block_sparse_index
-    q2k_block_sparse_index, _ = torch.sort(q2k_block_sparse_index, dim=-1)
-
-    # All q blocks attend to exactly k kv blocks
-    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks), k, dtype=torch.int32, device=device)
-    
-    # Create the corresponding mask
-    block_sparse_mask = torch.zeros(bs, h, num_q_blocks, num_kv_blocks, dtype=torch.bool, device=device)
-    
-    # Fill in the mask based on the indices
-    for b in range(bs):
-        for head in range(h):
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx]
-                block_sparse_mask[b, head, q_idx, kv_indices] = True
-    
-    # Create the reverse mapping (k2q)
-    # First, initialize lists to collect q indices for each kv block
-    k2q_indices_list = [[[] for _ in range(num_kv_blocks)] for _ in range(bs * h)]
-    
-    # Populate the lists based on q2k mapping
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx].tolist()
-                for kv_idx in kv_indices:
-                    k2q_indices_list[flat_idx][kv_idx].append(q_idx)
-    
-    # Find the maximum number of q blocks that attend to any kv block
-    max_q_per_kv = 0
-    for flat_idx in range(bs * h):
-        for kv_idx in range(num_kv_blocks):
-            max_q_per_kv = max(max_q_per_kv, len(k2q_indices_list[flat_idx][kv_idx]))
-    
-    # Create tensors for k2q mapping
-    k2q_block_sparse_index = torch.full((bs, h, num_kv_blocks, max_q_per_kv), -1, 
-                                        dtype=torch.int32, device=device)
-    k2q_block_sparse_num = torch.zeros((bs, h, num_kv_blocks), 
-                                       dtype=torch.int32, device=device)
-    
-    # Fill the tensors
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for kv_idx in range(num_kv_blocks):
-                q_indices = k2q_indices_list[flat_idx][kv_idx]
-                num_q = len(q_indices)
-                k2q_block_sparse_num[b, head, kv_idx] = num_q
-                if num_q > 0:
-                    k2q_block_sparse_index[b, head, kv_idx, :num_q] = torch.tensor(
-                        q_indices, dtype=torch.int32, device=device)
-                
-    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask
-
-def benchmark_block_sparse_attention(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, flops):
-    """Benchmark block sparse attention forward+backward pass."""
-    print("\n=== BLOCK SPARSE ATTENTION FORWARD+BACKWARD BENCHMARK ===")
-    
-    # Combined forward+backward pass
-    # Warm-up run
-    q_fwd = q.clone().requires_grad_(True)
-    k_fwd = k.clone().requires_grad_(True)
-    v_fwd = v.clone().requires_grad_(True)
-    o = block_sparse_attn(q_fwd, k_fwd, v_fwd, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num)
-    grad_output = torch.randn_like(o)
-    o.backward(grad_output)
-    torch.cuda.synchronize()
-    
-    # Benchmark forward+backward
-    def forward_backward_fn():
-        q_fwd = q.clone().requires_grad_(True)
-        k_fwd = k.clone().requires_grad_(True)
-        v_fwd = v.clone().requires_grad_(True)
-        o = block_sparse_attn(q_fwd, k_fwd, v_fwd, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num)
-        grad_output = torch.randn_like(o)
-        o.backward(grad_output)
-    
-    total_time = triton.testing.do_bench(
-        forward_backward_fn,
-        warmup=25,
-        rep=100,
-        return_mode='mean'
-    )
-    
-    # Total flops for forward + backward (forward + 2.5x backward approximation)
-    total_flops = flops + 2.5 * flops  # 3.5x the forward flops
-    sparse_tflops = total_flops / total_time * 1e-12 * 1e3
-    print(f"Block Sparse Forward+Backward - TFLOPS: {sparse_tflops:.2f}")
-    
-    return sparse_tflops
-
-def main():
-    args = parse_arguments()
-
-    set_seed(42)
-    
-    # Extract parameters
-    batch = args.batch_size
-    head = args.num_heads
-    headdim = args.head_dim
-    
-    print(f"Block Sparse Attention Benchmark")
-    print(f"batch: {batch}, head: {head}, headdim: {headdim}")
-    
-    # Test with different sequence lengths
-    for seq_len in args.seq_lengths:
-        # Skip very long sequences if they might cause OOM
-        if seq_len > 16384 and batch > 1:
-            continue
-            
-        print("="*100)
-        print(f"\nSequence length: {seq_len}")
-        
-        # Calculate theoretical FLOPs for attention
-        flops = 4 * batch * head * headdim * seq_len * seq_len
-        
-        # Create input tensors
-        q, k, v = create_input_tensors(batch, head, seq_len, headdim)
-        
-        # Setup block sparse parameters
-        num_q_blocks = seq_len // BLOCK_M
-        num_kv_blocks = seq_len // BLOCK_N
-        
-        # Determine k value (number of kv blocks per q block)
-        topk = args.topk
-        if topk is None:
-            topk = num_kv_blocks // 10  # Default to ~90% sparsity if k is not specified
-        topk = max(1, topk)       
-        print(f"Using topk={topk} kv blocks per q block (out of {num_kv_blocks} total kv blocks)")
-        
-        # Generate block sparse pattern
-        q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, _ = generate_block_sparse_pattern(
-            batch, head, num_q_blocks, num_kv_blocks, topk, device="cuda")
-        
-        # Benchmark block sparse attention
-        sparse_fwd = benchmark_block_sparse_attention(
-            q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, flops
-        )
-        
-        # Print results
-        print("\n=== PERFORMANCE RESULTS ===")
-        print(f"Block Sparse Forward+Backward - TFLOPS: {sparse_fwd:.2f}")
-
-if __name__ == "__main__":
-    main()

csrc/attn/config_sta.py

@@ -1,15 +0,0 @@
-### ADD TO THIS TO REGISTER NEW KERNELS
-sources = {
-    'st_attn': {
-        'source_files': {
-            'h100': 'st_attn/st_attn_h100.cu'  # define these source files for each GPU target desired.
-        }
-    }
-}
-
-### WHICH KERNELS DO WE WANT TO BUILD?
-# (oftentimes during development work you don't need to redefine them all.)
-kernels = ['st_attn']
-
-### WHICH GPU TARGET DO WE WANT TO BUILD FOR?
-target = 'h100'

csrc/attn/config_vsa.py

@@ -1,15 +0,0 @@
-### ADD TO THIS TO REGISTER NEW KERNELS
-sources = {
-    'block_sparse': {
-        'source_files': {
-            'h100': 'vsa/block_sparse_h100.cu'
-        }
-    }
-}
-
-### WHICH KERNELS DO WE WANT TO BUILD?
-# (oftentimes during development work you don't need to redefine them all.)
-kernels = ['block_sparse']
-
-### WHICH GPU TARGET DO WE WANT TO BUILD FOR?
-target = 'h100'

csrc/attn/scratch.sh

@@ -1,4 +0,0 @@
-    off_hz = tl.program_id(2)
-    b = off_hz // H
-    h = off_hz % H
-    meta_base = ((b * H + h) * q_tiles + q_blk)

csrc/attn/setup_sta.py

@@ -1,76 +0,0 @@
-import os
-import subprocess
-
-from csrc.attn.config_sta import kernels, sources, target
-from setuptools import find_packages, setup
-from torch.utils.cpp_extension import BuildExtension, CUDAExtension
-
-target = target.lower()
-
-# Package metadata
-PACKAGE_NAME = "st_attn"
-VERSION = "0.0.4"
-AUTHOR = "Hao AI Lab"
-DESCRIPTION = "Sliding Tile Atteniton Kernel Used in FastVideo"
-URL = "https://github.com/hao-ai-lab/FastVideo/tree/main/csrc/sliding_tile_attention"
-
-# Set environment variables
-tk_root = os.getenv('THUNDERKITTENS_ROOT', os.path.abspath(os.path.join(os.getcwd(), 'tk/')))
-python_include = subprocess.check_output(['python', '-c',
-                                          "import sysconfig; print(sysconfig.get_path('include'))"]).decode().strip()
-torch_include = subprocess.check_output([
-    'python', '-c',
-    "import torch; from torch.utils.cpp_extension import include_paths; print(' '.join(['-I' + p for p in include_paths()]))"
-]).decode().strip()
-print('st_attn root:', tk_root)
-print('Python include:', python_include)
-print('Torch include directories:', torch_include)
-
-# CUDA flags
-cuda_flags = [
-    '-DNDEBUG', '-Xcompiler=-Wno-psabi', '-Xcompiler=-fno-strict-aliasing', '--expt-extended-lambda',
-    '--expt-relaxed-constexpr', '-forward-unknown-to-host-compiler', '--use_fast_math', '-std=c++20', '-O3',
-    '-Xnvlink=--verbose', '-Xptxas=--verbose', '-Xptxas=--warn-on-spills', f'-I{tk_root}/include',
-    f'-I{tk_root}/prototype', f'-I{python_include}', '-DTORCH_COMPILE'
-] + torch_include.split()
-cpp_flags = ['-std=c++20', '-O3']
-
-if target == 'h100':
-    cuda_flags.append('-DKITTENS_HOPPER')
-    cuda_flags.append('-arch=sm_90a')
-else:
-    raise ValueError(f'Target {target} not supported')
-
-source_files = ['st_attn.cpp']
-for k in kernels:
-    if target not in sources[k]['source_files']:
-        raise KeyError(f'Target {target} not found in source files for kernel {k}')
-    if isinstance(sources[k]['source_files'][target], list):
-        source_files.extend(sources[k]['source_files'][target])
-    else:
-        source_files.append(sources[k]['source_files'][target])
-    cpp_flags.append(f'-DTK_COMPILE_{k.replace(" ", "_").upper()}')
-
-setup(name=PACKAGE_NAME,
-      version=VERSION,
-      author=AUTHOR,
-      description=DESCRIPTION,
-      url=URL,
-      packages=find_packages(),
-      ext_modules=[
-          CUDAExtension('st_attn_cuda',
-                        sources=source_files,
-                        extra_compile_args={
-                            'cxx': cpp_flags,
-                            'nvcc': cuda_flags
-                        },
-                        libraries=['cuda'])
-      ],
-      cmdclass={'build_ext': BuildExtension},
-      classifiers=[
-          "Programming Language :: Python :: 3",
-          "Environment :: GPU :: NVIDIA CUDA :: 12",
-          "License :: OSI Approved :: Apache Software License",
-      ],
-      python_requires='>=3.10',
-      install_requires=["torch>=2.5.0"])

csrc/attn/setup_vsa.py

@@ -1,84 +0,0 @@
-import os
-import subprocess
-
-from config_vsa import kernels, sources, target
-from setuptools import find_packages, setup
-from torch.utils.cpp_extension import BuildExtension, CUDAExtension
-
-target = target.lower()
-
-# Package metadata
-PACKAGE_NAME = "vsa"
-VERSION = "0.0.1"
-AUTHOR = "Hao AI Lab"
-DESCRIPTION = "Video Sparse Attention Kernel Used in FastVideo"
-URL = "https://github.com/hao-ai-lab/FastVideo/tree/main/csrc/attn"
-
-# Set environment variables
-tk_root = os.getenv('THUNDERKITTENS_ROOT', os.path.abspath(os.path.join(os.getcwd(), 'tk/')))
-python_include = subprocess.check_output(['python', '-c',
-                                          "import sysconfig; print(sysconfig.get_path('include'))"]).decode().strip()
-torch_include = subprocess.check_output([
-    'python', '-c',
-    "import torch; from torch.utils.cpp_extension import include_paths; print(' '.join(['-I' + p for p in include_paths()]))"
-]).decode().strip()
-print('vsa root:', tk_root)
-print('Python include:', python_include)
-print('Torch include directories:', torch_include)
-
-# CUDA flags
-cuda_flags = [
-    '-DNDEBUG', '-Xcompiler=-Wno-psabi', '-Xcompiler=-fno-strict-aliasing', '--expt-extended-lambda',
-    '--expt-relaxed-constexpr', '-forward-unknown-to-host-compiler', '--use_fast_math', '-std=c++20', '-O3',
-    '-Xnvlink=--verbose', '-Xptxas=--verbose', '-Xptxas=--warn-on-spills', f'-I{tk_root}/include',
-    f'-I{tk_root}/prototype', f'-I{python_include}', '-DTORCH_COMPILE'
-] + torch_include.split()
-cpp_flags = ['-std=c++20', '-O3']
-
-if target == 'h100':
-    cuda_flags.append('-DKITTENS_HOPPER')
-    cuda_flags.append('-arch=sm_90a')
-else:
-    raise ValueError(f'Target {target} not supported')
-
-source_files = ['vsa.cpp']
-for k in kernels:
-    if target not in sources[k]['source_files']:
-        raise KeyError(f'Target {target} not found in source files for kernel {k}')
-    if isinstance(sources[k]['source_files'][target], list):
-        source_files.extend(sources[k]['source_files'][target])
-    else:
-        source_files.append(sources[k]['source_files'][target])
-    cpp_flags.append(f'-DTK_COMPILE_{k.replace(" ", "_").upper()}')
-
-ext_modules = []
-import torch
-major, minor = torch.cuda.get_device_capability(0)
-if major == 9 and minor == 0:# check if H100
-    ext_modules = [
-        CUDAExtension('vsa_cuda',
-            sources=source_files,
-            extra_compile_args={
-                'cxx': cpp_flags,
-                'nvcc': cuda_flags
-            },
-            libraries=['cuda'])
-    ]
-
-
-
-setup(name=PACKAGE_NAME,
-      version=VERSION,
-      author=AUTHOR,
-      description=DESCRIPTION,
-      url=URL,
-      packages=find_packages(),
-      ext_modules=ext_modules,
-      cmdclass={'build_ext': BuildExtension},
-      classifiers=[
-          "Programming Language :: Python :: 3",
-          "Environment :: GPU :: NVIDIA CUDA :: 12",
-          "License :: OSI Approved :: Apache Software License",
-      ],
-      python_requires='>=3.10',
-      install_requires=["torch>=2.5.0"])

csrc/attn/st_attn.cpp

@@ -1,23 +0,0 @@
-#include <torch/extension.h>
-#include <ATen/ATen.h>
-
-#include <vector>
-#include <cuda_fp16.h>
-#include <cuda_bf16.h>
-
-#include <cuda_runtime.h>
-
-#ifdef TK_COMPILE_ST_ATTN
-extern torch::Tensor sta_forward(
-    torch::Tensor q, torch::Tensor k, torch::Tensor v, torch::Tensor o, int kernel_t_size, int kernel_w_size, int kernel_h_size, int text_length, bool process_text, bool has_text, int kernel_aspect_ratio_flag
-); 
-#endif
-
-
-PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
-    m.doc() = "Sliding Block Attention Kernels"; // optional module docstring
-    
-#ifdef TK_COMPILE_ST_ATTN
-    m.def("sta_fwd",  torch::wrap_pybind_function(sta_forward), "sliding tile attention, assuming tile size is (6,8,8)");
-#endif
-}

csrc/attn/st_attn/__init__.py

@@ -1,49 +0,0 @@
-import math
-
-import torch
-from torch.utils.checkpoint import detach_variable
-try:
-    from st_attn_cuda import sta_fwd
-except ImportError:
-    sta_fwd = None
-
-def sliding_tile_attention(q_all, k_all, v_all, window_size, text_length, has_text=True, dit_seq_shape='30x48x80'):
-    seq_length = q_all.shape[2]
-    dit_seq_shape_mapping = {
-        '30x48x80':1,
-        '36x48x48':2,
-        '18x48x80':3, 
-    }
-    if has_text:
-        assert q_all.shape[
-            2] >= 115200 and q_all.shape[2] <= 115456, f"Unsupported {dit_seq_shape}, current shape is {q_all.shape}, only support '30x48x80' for HunyuanVideo"
-        assert q_all.shape[1] == len(window_size), "Number of heads must match the number of window sizes"
-        target_size = math.ceil(seq_length / 384) * 384
-        pad_size = target_size - seq_length
-        if pad_size > 0:
-            q_all = torch.cat([q_all, q_all[:, :, -pad_size:]], dim=2)
-            k_all = torch.cat([k_all, k_all[:, :, -pad_size:]], dim=2)
-            v_all = torch.cat([v_all, v_all[:, :, -pad_size:]], dim=2)
-    else:
-        if dit_seq_shape == '36x48x48': # Stepvideo 204x768x68
-            assert q_all.shape[2] == 82944
-        elif dit_seq_shape == '18x48x80': # Wan 69x768x1280
-            assert q_all.shape[2] == 69120
-        else:
-            raise ValueError(f"Unsupported {dit_seq_shape}, current shape is {q_all.shape}, only support '36x48x48' for Stepvideo and '18x48x80' for Wan")
-
-    kernel_aspect_ratio_flag = dit_seq_shape_mapping[dit_seq_shape]
-    hidden_states = torch.empty_like(q_all)
-    # This for loop is ugly. but it is actually quite efficient. The sequence dimension alone can already oversubscribe SMs
-    for head_index, (t_kernel, h_kernel, w_kernel) in enumerate(window_size):
-        for batch in range(q_all.shape[0]):
-            q_head, k_head, v_head, o_head = (q_all[batch:batch + 1, head_index:head_index + 1],
-                                              k_all[batch:batch + 1,
-                                                    head_index:head_index + 1], v_all[batch:batch + 1,
-                                                                                      head_index:head_index + 1],
-                                              hidden_states[batch:batch + 1, head_index:head_index + 1])
-
-            _ = sta_fwd(q_head, k_head, v_head, o_head, t_kernel, h_kernel, w_kernel, text_length, False, has_text, kernel_aspect_ratio_flag)
-    if has_text:
-        _ = sta_fwd(q_all, k_all, v_all, hidden_states, 3, 3, 3, text_length, True, True, kernel_aspect_ratio_flag)
-    return hidden_states[:, :, :seq_length]

csrc/attn/tests/test_block_sparse.py

@@ -1,289 +0,0 @@
-import torch
-import argparse
-from flash_attn.utils.benchmark import benchmark_forward
-from flash_attn import flash_attn_func
-from vsa import block_sparse_attn
-from vsa import BLOCK_M, BLOCK_N
-
-import numpy as np
-import random
-import gc
-
-def set_seed(seed: int = 42):
-    # Python random module
-    random.seed(seed)
-
-    # NumPy
-    np.random.seed(seed)
-
-    # PyTorch
-    torch.manual_seed(seed)
-    torch.cuda.manual_seed(seed)
-    torch.cuda.manual_seed_all(seed)  # if using multi-GPU
-
-
-@torch.no_grad
-def precision_metric(quant_o, fa2_o): 
-    x, xx = quant_o.float(), fa2_o.float() 
-    sim = torch.nn.functional.cosine_similarity(x.reshape(1, -1), xx.reshape(1, -1)).item()
-    l1 =   ((x - xx).abs().sum() / xx.abs().sum() ).item()
-    rmse = torch.sqrt(torch.mean((x -xx) ** 2)).item()
-
-    return sim, l1, rmse
-
-def create_input_tensors(batch, head, seq_len, headdim):
-    """Create random input tensors for attention."""
-    q = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    k = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    v = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    return q, k, v
-
-def generate_block_sparse_pattern(bs, h, num_q_blocks, num_kv_blocks, k, device="cuda"):
-    """
-    Generate a block sparse pattern where each q block attends to exactly k kv blocks.
-    
-    Args:
-        bs: batch size
-        h: number of heads
-        num_q_blocks: number of query blocks
-        num_kv_blocks: number of key-value blocks
-        k: number of kv blocks each q block attends to
-        device: device to create tensors on
-        
-    Returns:
-        q2k_block_sparse_index: [bs, h, num_q_blocks, k]
-            Contains the indices of kv blocks that each q block attends to.
-        q2k_block_sparse_num: [bs, h, num_q_blocks]
-            Contains the number of kv blocks that each q block attends to (all equal to k).
-        k2q_block_sparse_index: [bs, h, num_kv_blocks, num_q_blocks]
-            Contains the indices of q blocks that attend to each kv block.
-        k2q_block_sparse_num: [bs, h, num_kv_blocks]
-            Contains the number of q blocks that attend to each kv block.
-        block_sparse_mask: [bs, h, num_q_blocks, num_kv_blocks]
-            Binary mask where 1 indicates attention connection.
-    """
-    # Ensure k is not larger than num_kv_blocks
-    k = min(k, num_kv_blocks)
-    
-    # Create random scores for sampling
-    scores = torch.rand(bs, h, num_q_blocks, num_kv_blocks, device=device)
-    
-    # Get top-k indices for each q block
-    _, q2k_block_sparse_index = torch.topk(scores, k, dim=-1)
-    q2k_block_sparse_index = q2k_block_sparse_index.to(torch.int32)
-
-    # sort q2k_block_sparse_index
-    q2k_block_sparse_index, _ = torch.sort(q2k_block_sparse_index, dim=-1)
-
-    # All q blocks attend to exactly k kv blocks
-    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks), k, dtype=torch.int32, device=device)
-    
-    # Create the corresponding mask
-    block_sparse_mask = torch.zeros(bs, h, num_q_blocks, num_kv_blocks, dtype=torch.bool, device=device)
-    
-    # Fill in the mask based on the indices
-    for b in range(bs):
-        for head in range(h):
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx]
-                block_sparse_mask[b, head, q_idx, kv_indices] = True
-    
-    # Create the reverse mapping (k2q)
-    # First, initialize lists to collect q indices for each kv block
-    k2q_indices_list = [[[] for _ in range(num_kv_blocks)] for _ in range(bs * h)]
-    
-    # Populate the lists based on q2k mapping
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx].tolist()
-                for kv_idx in kv_indices:
-                    k2q_indices_list[flat_idx][kv_idx].append(q_idx)
-    
-    # Find the maximum number of q blocks that attend to any kv block
-    max_q_per_kv = 0
-    for flat_idx in range(bs * h):
-        for kv_idx in range(num_kv_blocks):
-            max_q_per_kv = max(max_q_per_kv, len(k2q_indices_list[flat_idx][kv_idx]))
-    
-    # Create tensors for k2q mapping
-    k2q_block_sparse_index = torch.full((bs, h, num_kv_blocks, max_q_per_kv), -1, 
-                                        dtype=torch.int32, device=device)
-    k2q_block_sparse_num = torch.zeros((bs, h, num_kv_blocks), 
-                                       dtype=torch.int32, device=device)
-    
-    # Fill the tensors
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for kv_idx in range(num_kv_blocks):
-                q_indices = k2q_indices_list[flat_idx][kv_idx]
-                num_q = len(q_indices)
-                k2q_block_sparse_num[b, head, kv_idx] = num_q
-                if num_q > 0:
-                    k2q_block_sparse_index[b, head, kv_idx, :num_q] = torch.tensor(
-                        q_indices, dtype=torch.int32, device=device)
-                
-    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask
-
-def main(args):
-    set_seed(42)
-    
-    # Extract parameters
-    batch = args.batch_size
-    head = args.num_heads
-    headdim = args.head_dim
-    num_iterations = args.num_iterations
-    
-    print(f"Block Sparse Attention Benchmark")
-    print(f"batch: {batch}, head: {head}, headdim: {headdim}, iterations: {num_iterations}")
-    
-    # Test with different sequence lengths
-    for seq_len in args.seq_lengths:
-        # Skip very long sequences if they might cause OOM
-        # if seq_len > 16384 and batch > 1:
-        #     continue
-            
-        print("="*100)
-        print(f"\nSequence length: {seq_len}")
-        
-        # Collect metrics across iterations
-        forward_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        grad_q_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        grad_k_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        grad_v_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        
-        for iter_idx in range(num_iterations):
-            if num_iterations > 1:
-                print(f"\nIteration {iter_idx+1}/{num_iterations}")
-            
-            # Create input tensors
-            q, k, v = create_input_tensors(batch, head, seq_len, headdim)
-            
-            # Setup block sparse parameters
-            num_q_blocks = seq_len // BLOCK_M
-            num_kv_blocks = seq_len // BLOCK_N
-            
-            # Determine k value (number of kv blocks per q block)
-            topk = args.topk
-            if topk is None:
-                topk = num_kv_blocks // 10  # Default to ~90% sparsity if k is not specified
-            topk = max(1, topk)
-            if iter_idx == 0:  # Only print this once
-                print(f"Using topk={topk} kv blocks per q block (out of {num_kv_blocks} total kv blocks)")
-
-            # Generate block sparse pattern
-            q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask = generate_block_sparse_pattern(
-                batch, head, num_q_blocks, num_kv_blocks, topk, device="cuda")
-
-            # expand block_sparse_mask to full mask
-            block_mask_expanded = block_sparse_mask.unsqueeze(-1).unsqueeze(-2)  # [b, h, num_q_blocks, num_kv_blocks, 1, 1]
-            block_mask_expanded = block_mask_expanded.expand(-1, -1, -1, -1, BLOCK_M, BLOCK_N)  # [b, h, num_q_blocks, num_kv_blocks, BLOCK_M, BLOCK_N]
-            full_mask = block_mask_expanded.permute(0, 1, 2, 4, 3, 5).reshape(batch, head, seq_len, seq_len)
-
-            q.requires_grad = True
-            k.requires_grad = True
-            v.requires_grad = True
-
-
-            # testing forward
-            o = block_sparse_attn(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num)
-            del q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask, block_mask_expanded
-            grad_o = torch.randn_like(o)
-            o.backward(grad_o)
-            # clear memory
-            q_sdpa = q.detach().clone()
-            k_sdpa = k.detach().clone()
-            v_sdpa = v.detach().clone()
-            q_sdpa.requires_grad = True
-            k_sdpa.requires_grad = True
-            v_sdpa.requires_grad = True
-            q.data = torch.empty(0, device=q.device)
-            k.data = torch.empty(0, device=k.device)
-            v.data = torch.empty(0, device=v.device)
-            torch.cuda.empty_cache()
-
-            o_sdpa = torch.nn.functional.scaled_dot_product_attention(q_sdpa, k_sdpa, v_sdpa, attn_mask=full_mask)
-
-
-            sim, l1, rmse = precision_metric(o, o_sdpa)
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 8e-5, f"l1 too large: {l1}"
-            assert rmse < 2e-5, f"RMSE too large: {rmse}"
-            forward_metrics['sim'].append(sim)
-            forward_metrics['l1'].append(l1)
-            forward_metrics['rmse'].append(rmse)
-
-            print(f"block_sparse_fwd vs torch.nn.functional.scaled_dot_product_attention:\nsim: {sim}, l1: {l1}, rmse: {rmse}")
-
-            # test backward
-            o_sdpa.backward(grad_o)
-
-            sim, l1, rmse = precision_metric(q.grad, q_sdpa.grad)
-            # Error bounds collected on H100
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 4e-3, f"l1 too large: {l1}"
-            assert rmse < 3e-4, f"RMSE too large: {rmse}"
-            grad_q_metrics['sim'].append(sim)
-            grad_q_metrics['l1'].append(l1)
-            grad_q_metrics['rmse'].append(rmse)
-            print(f"block_sparse_bwd vs torch.nn.functional.scaled_dot_product_attention grad_q:\nsim: {sim}, l1: {l1}, rmse: {rmse}")        
-            
-            sim, l1, rmse = precision_metric(k.grad, k_sdpa.grad)
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 4e-3, f"l1 too large: {l1}"
-            assert rmse < 2e-4, f"RMSE too large: {rmse}"
-            grad_k_metrics['sim'].append(sim)
-            grad_k_metrics['l1'].append(l1)
-            grad_k_metrics['rmse'].append(rmse)
-            print(f"block_sparse_bwd vs torch.nn.functional.scaled_dot_product_attention grad_k:\nsim: {sim}, l1: {l1}, rmse: {rmse}")
-            
-            sim, l1, rmse = precision_metric(v.grad, v_sdpa.grad)
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 1e-4, f"l1 too large: {l1}"
-            assert rmse < 2e-5, f"RMSE too large: {rmse}"
-            grad_v_metrics['sim'].append(sim)
-            grad_v_metrics['l1'].append(l1)
-            grad_v_metrics['rmse'].append(rmse)
-            print(f"block_sparse_bwd vs torch.nn.functional.scaled_dot_product_attention grad_v:\nsim: {sim}, l1: {l1}, rmse: {rmse}")
-            
-            del o, o_sdpa, grad_o, q_sdpa, k_sdpa, v_sdpa
-            gc.collect()
-            torch.cuda.empty_cache()
-
-        # Print summary statistics if multiple iterations were run
-        if num_iterations > 1:
-            print("\n" + "="*50)
-            print(f"Summary Statistics (over {num_iterations} iterations):")
-            
-            print("\nForward metrics:")
-            print(f"Similarity: mean={np.mean(forward_metrics['sim']):.6f}, std={np.std(forward_metrics['sim']):.6f}, min={np.min(forward_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(forward_metrics['l1']):.6f}, std={np.std(forward_metrics['l1']):.6f}, max={np.max(forward_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(forward_metrics['rmse']):.6f}, std={np.std(forward_metrics['rmse']):.6f}, max={np.max(forward_metrics['rmse']):.6f}")
-            
-            print("\nGradient Q metrics:")
-            print(f"Similarity: mean={np.mean(grad_q_metrics['sim']):.6f}, std={np.std(grad_q_metrics['sim']):.6f}, min={np.min(grad_q_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(grad_q_metrics['l1']):.6f}, std={np.std(grad_q_metrics['l1']):.6f}, max={np.max(grad_q_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(grad_q_metrics['rmse']):.6f}, std={np.std(grad_q_metrics['rmse']):.6f}, max={np.max(grad_q_metrics['rmse']):.6f}")
-            
-            print("\nGradient K metrics:")
-            print(f"Similarity: mean={np.mean(grad_k_metrics['sim']):.6f}, std={np.std(grad_k_metrics['sim']):.6f}, min={np.min(grad_k_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(grad_k_metrics['l1']):.6f}, std={np.std(grad_k_metrics['l1']):.6f}, max={np.max(grad_k_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(grad_k_metrics['rmse']):.6f}, std={np.std(grad_k_metrics['rmse']):.6f}, max={np.max(grad_k_metrics['rmse']):.6f}")
-            
-            print("\nGradient V metrics:")
-            print(f"Similarity: mean={np.mean(grad_v_metrics['sim']):.6f}, std={np.std(grad_v_metrics['sim']):.6f}, min={np.min(grad_v_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(grad_v_metrics['l1']):.6f}, std={np.std(grad_v_metrics['l1']):.6f}, max={np.max(grad_v_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(grad_v_metrics['rmse']):.6f}, std={np.std(grad_v_metrics['rmse']):.6f}, max={np.max(grad_v_metrics['rmse']):.6f}")
-
-if __name__ == "__main__":
-    parser = argparse.ArgumentParser(description='Benchmark Block Sparse Attention')
-    parser.add_argument('--batch_size', type=int, default=4, help='Batch size')
-    parser.add_argument('--num_heads', type=int, default=6, help='Number of heads')
-    parser.add_argument('--head_dim', type=int, default=128, help='Head dimension')
-    parser.add_argument('--topk', type=int, default=64, help='Number of kv blocks each q block attends to')
-    parser.add_argument('--seq_lengths', type=int, nargs='+', default=[29120], help='Sequence lengths to benchmark')
-    parser.add_argument('--num_iterations', type=int, default=50, help='Number of test iterations to run')
-    args = parser.parse_args()
-    main(args)

csrc/attn/tests/test_block_sparse_triton.py

@@ -1,289 +0,0 @@
-import torch
-import argparse
-from flash_attn.utils.benchmark import benchmark_forward
-from flash_attn import flash_attn_func
-from vsa import triton_attention_sparse
-from vsa import BLOCK_M, BLOCK_N
-
-import numpy as np
-import random
-import gc
-
-def set_seed(seed: int = 42):
-    # Python random module
-    random.seed(seed)
-
-    # NumPy
-    np.random.seed(seed)
-
-    # PyTorch
-    torch.manual_seed(seed)
-    torch.cuda.manual_seed(seed)
-    torch.cuda.manual_seed_all(seed)  # if using multi-GPU
-
-
-@torch.no_grad
-def precision_metric(quant_o, fa2_o): 
-    x, xx = quant_o.float(), fa2_o.float() 
-    sim = torch.nn.functional.cosine_similarity(x.reshape(1, -1), xx.reshape(1, -1)).item()
-    l1 =   ((x - xx).abs().sum() / xx.abs().sum() ).item()
-    rmse = torch.sqrt(torch.mean((x -xx) ** 2)).item()
-
-    return sim, l1, rmse
-
-def create_input_tensors(batch, head, seq_len, headdim):
-    """Create random input tensors for attention."""
-    q = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    k = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    v = torch.randn(batch, head, seq_len, headdim, dtype=torch.bfloat16, device="cuda")
-    return q, k, v
-
-def generate_block_sparse_pattern(bs, h, num_q_blocks, num_kv_blocks, k, device="cuda"):
-    """
-    Generate a block sparse pattern where each q block attends to exactly k kv blocks.
-    
-    Args:
-        bs: batch size
-        h: number of heads
-        num_q_blocks: number of query blocks
-        num_kv_blocks: number of key-value blocks
-        k: number of kv blocks each q block attends to
-        device: device to create tensors on
-        
-    Returns:
-        q2k_block_sparse_index: [bs, h, num_q_blocks, k]
-            Contains the indices of kv blocks that each q block attends to.
-        q2k_block_sparse_num: [bs, h, num_q_blocks]
-            Contains the number of kv blocks that each q block attends to (all equal to k).
-        k2q_block_sparse_index: [bs, h, num_kv_blocks, num_q_blocks]
-            Contains the indices of q blocks that attend to each kv block.
-        k2q_block_sparse_num: [bs, h, num_kv_blocks]
-            Contains the number of q blocks that attend to each kv block.
-        block_sparse_mask: [bs, h, num_q_blocks, num_kv_blocks]
-            Binary mask where 1 indicates attention connection.
-    """
-    # Ensure k is not larger than num_kv_blocks
-    k = min(k, num_kv_blocks)
-    
-    # Create random scores for sampling
-    scores = torch.rand(bs, h, num_q_blocks, num_kv_blocks, device=device)
-    
-    # Get top-k indices for each q block
-    _, q2k_block_sparse_index = torch.topk(scores, k, dim=-1)
-    q2k_block_sparse_index = q2k_block_sparse_index.to(torch.int32)
-
-    # sort q2k_block_sparse_index
-    q2k_block_sparse_index, _ = torch.sort(q2k_block_sparse_index, dim=-1)
-
-    # All q blocks attend to exactly k kv blocks
-    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks), k, dtype=torch.int32, device=device)
-    
-    # Create the corresponding mask
-    block_sparse_mask = torch.zeros(bs, h, num_q_blocks, num_kv_blocks, dtype=torch.bool, device=device)
-    
-    # Fill in the mask based on the indices
-    for b in range(bs):
-        for head in range(h):
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx]
-                block_sparse_mask[b, head, q_idx, kv_indices] = True
-    
-    # Create the reverse mapping (k2q)
-    # First, initialize lists to collect q indices for each kv block
-    k2q_indices_list = [[[] for _ in range(num_kv_blocks)] for _ in range(bs * h)]
-    
-    # Populate the lists based on q2k mapping
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for q_idx in range(num_q_blocks):
-                kv_indices = q2k_block_sparse_index[b, head, q_idx].tolist()
-                for kv_idx in kv_indices:
-                    k2q_indices_list[flat_idx][kv_idx].append(q_idx)
-    
-    # Find the maximum number of q blocks that attend to any kv block
-    max_q_per_kv = 0
-    for flat_idx in range(bs * h):
-        for kv_idx in range(num_kv_blocks):
-            max_q_per_kv = max(max_q_per_kv, len(k2q_indices_list[flat_idx][kv_idx]))
-    
-    # Create tensors for k2q mapping
-    k2q_block_sparse_index = torch.full((bs, h, num_kv_blocks, max_q_per_kv), -1, 
-                                        dtype=torch.int32, device=device)
-    k2q_block_sparse_num = torch.zeros((bs, h, num_kv_blocks), 
-                                       dtype=torch.int32, device=device)
-    
-    # Fill the tensors
-    for b in range(bs):
-        for head in range(h):
-            flat_idx = b * h + head
-            for kv_idx in range(num_kv_blocks):
-                q_indices = k2q_indices_list[flat_idx][kv_idx]
-                num_q = len(q_indices)
-                k2q_block_sparse_num[b, head, kv_idx] = num_q
-                if num_q > 0:
-                    k2q_block_sparse_index[b, head, kv_idx, :num_q] = torch.tensor(
-                        q_indices, dtype=torch.int32, device=device)
-                
-    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask
-
-def main(args):
-    set_seed(42)
-    
-    # Extract parameters
-    batch = args.batch_size
-    head = args.num_heads
-    headdim = args.head_dim
-    num_iterations = args.num_iterations
-    
-    print(f"Block Sparse Attention Benchmark")
-    print(f"batch: {batch}, head: {head}, headdim: {headdim}, iterations: {num_iterations}")
-    
-    # Test with different sequence lengths
-    for seq_len in args.seq_lengths:
-        # Skip very long sequences if they might cause OOM
-        # if seq_len > 16384 and batch > 1:
-        #     continue
-            
-        print("="*100)
-        print(f"\nSequence length: {seq_len}")
-        
-        # Collect metrics across iterations
-        forward_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        grad_q_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        grad_k_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        grad_v_metrics = {'sim': [], 'l1': [], 'rmse': []}
-        
-        for iter_idx in range(num_iterations):
-            if num_iterations > 1:
-                print(f"\nIteration {iter_idx+1}/{num_iterations}")
-            
-            # Create input tensors
-            q, k, v = create_input_tensors(batch, head, seq_len, headdim)
-            
-            # Setup block sparse parameters
-            num_q_blocks = seq_len // BLOCK_M
-            num_kv_blocks = seq_len // BLOCK_N
-            
-            # Determine k value (number of kv blocks per q block)
-            topk = args.topk
-            if topk is None:
-                topk = num_kv_blocks // 10  # Default to ~90% sparsity if k is not specified
-            topk = max(1, topk)
-            if iter_idx == 0:  # Only print this once
-                print(f"Using topk={topk} kv blocks per q block (out of {num_kv_blocks} total kv blocks)")
-
-            # Generate block sparse pattern
-            q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask = generate_block_sparse_pattern(
-                batch, head, num_q_blocks, num_kv_blocks, topk, device="cuda")
-
-            # expand block_sparse_mask to full mask
-            block_mask_expanded = block_sparse_mask.unsqueeze(-1).unsqueeze(-2)  # [b, h, num_q_blocks, num_kv_blocks, 1, 1]
-            block_mask_expanded = block_mask_expanded.expand(-1, -1, -1, -1, BLOCK_M, BLOCK_N)  # [b, h, num_q_blocks, num_kv_blocks, BLOCK_M, BLOCK_N]
-            full_mask = block_mask_expanded.permute(0, 1, 2, 4, 3, 5).reshape(batch, head, seq_len, seq_len)
-
-            q.requires_grad = True
-            k.requires_grad = True
-            v.requires_grad = True
-
-
-            # testing forward
-            o = triton_attention_sparse(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num)
-            del q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num, block_sparse_mask, block_mask_expanded
-            grad_o = torch.randn_like(o)
-            o.backward(grad_o)
-            # clear memory
-            q_sdpa = q.detach().clone()
-            k_sdpa = k.detach().clone()
-            v_sdpa = v.detach().clone()
-            q_sdpa.requires_grad = True
-            k_sdpa.requires_grad = True
-            v_sdpa.requires_grad = True
-            q.data = torch.empty(0, device=q.device)
-            k.data = torch.empty(0, device=k.device)
-            v.data = torch.empty(0, device=v.device)
-            torch.cuda.empty_cache()
-
-            o_sdpa = torch.nn.functional.scaled_dot_product_attention(q_sdpa, k_sdpa, v_sdpa, attn_mask=full_mask)
-
-
-            sim, l1, rmse = precision_metric(o, o_sdpa)
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 8e-5, f"l1 too large: {l1}"
-            assert rmse < 5e-5, f"RMSE too large: {rmse}"
-            forward_metrics['sim'].append(sim)
-            forward_metrics['l1'].append(l1)
-            forward_metrics['rmse'].append(rmse)
-
-            print(f"block_sparse_attention_fwd vs torch.nn.functional.scaled_dot_product_attention:\nsim: {sim}, l1: {l1}, rmse: {rmse}")
-
-            # test backward
-            o_sdpa.backward(grad_o)
-
-            sim, l1, rmse = precision_metric(q.grad, q_sdpa.grad)
-            # Error bounds collected on H100
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 4e-3, f"l1 too large: {l1}"
-            assert rmse < 5e-4, f"RMSE too large: {rmse}"
-            grad_q_metrics['sim'].append(sim)
-            grad_q_metrics['l1'].append(l1)
-            grad_q_metrics['rmse'].append(rmse)
-            print(f"block_sparse_attention_bwd vs torch.nn.functional.scaled_dot_product_attention grad_q:\nsim: {sim}, l1: {l1}, rmse: {rmse}")        
-            
-            sim, l1, rmse = precision_metric(k.grad, k_sdpa.grad)
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 4e-3, f"l1 too large: {l1}"
-            assert rmse < 5e-4, f"RMSE too large: {rmse}"
-            grad_k_metrics['sim'].append(sim)
-            grad_k_metrics['l1'].append(l1)
-            grad_k_metrics['rmse'].append(rmse)
-            print(f"block_sparse_attention_bwd vs torch.nn.functional.scaled_dot_product_attention grad_k:\nsim: {sim}, l1: {l1}, rmse: {rmse}")
-            
-            sim, l1, rmse = precision_metric(v.grad, v_sdpa.grad)
-            assert sim > 0.9999, f"SSIM too low: {sim}"
-            assert l1 < 4e-3, f"l1 too large: {l1}"
-            assert rmse < 5e-4, f"RMSE too large: {rmse}"
-            grad_v_metrics['sim'].append(sim)
-            grad_v_metrics['l1'].append(l1)
-            grad_v_metrics['rmse'].append(rmse)
-            print(f"block_sparse_attention_bwd vs torch.nn.functional.scaled_dot_product_attention grad_v:\nsim: {sim}, l1: {l1}, rmse: {rmse}")
-            
-            del o, o_sdpa, grad_o, q_sdpa, k_sdpa, v_sdpa
-            gc.collect()
-            torch.cuda.empty_cache()
-
-        # Print summary statistics if multiple iterations were run
-        if num_iterations > 1:
-            print("\n" + "="*50)
-            print(f"Summary Statistics (over {num_iterations} iterations):")
-            
-            print("\nForward metrics:")
-            print(f"Similarity: mean={np.mean(forward_metrics['sim']):.6f}, std={np.std(forward_metrics['sim']):.6f}, min={np.min(forward_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(forward_metrics['l1']):.6f}, std={np.std(forward_metrics['l1']):.6f}, max={np.max(forward_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(forward_metrics['rmse']):.6f}, std={np.std(forward_metrics['rmse']):.6f}, max={np.max(forward_metrics['rmse']):.6f}")
-            
-            print("\nGradient Q metrics:")
-            print(f"Similarity: mean={np.mean(grad_q_metrics['sim']):.6f}, std={np.std(grad_q_metrics['sim']):.6f}, min={np.min(grad_q_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(grad_q_metrics['l1']):.6f}, std={np.std(grad_q_metrics['l1']):.6f}, max={np.max(grad_q_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(grad_q_metrics['rmse']):.6f}, std={np.std(grad_q_metrics['rmse']):.6f}, max={np.max(grad_q_metrics['rmse']):.6f}")
-            
-            print("\nGradient K metrics:")
-            print(f"Similarity: mean={np.mean(grad_k_metrics['sim']):.6f}, std={np.std(grad_k_metrics['sim']):.6f}, min={np.min(grad_k_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(grad_k_metrics['l1']):.6f}, std={np.std(grad_k_metrics['l1']):.6f}, max={np.max(grad_k_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(grad_k_metrics['rmse']):.6f}, std={np.std(grad_k_metrics['rmse']):.6f}, max={np.max(grad_k_metrics['rmse']):.6f}")
-            
-            print("\nGradient V metrics:")
-            print(f"Similarity: mean={np.mean(grad_v_metrics['sim']):.6f}, std={np.std(grad_v_metrics['sim']):.6f}, min={np.min(grad_v_metrics['sim']):.6f}")
-            print(f"L1 error: mean={np.mean(grad_v_metrics['l1']):.6f}, std={np.std(grad_v_metrics['l1']):.6f}, max={np.max(grad_v_metrics['l1']):.6f}")
-            print(f"RMSE: mean={np.mean(grad_v_metrics['rmse']):.6f}, std={np.std(grad_v_metrics['rmse']):.6f}, max={np.max(grad_v_metrics['rmse']):.6f}")
-
-if __name__ == "__main__":
-    parser = argparse.ArgumentParser(description='Benchmark Block Sparse Attention')
-    parser.add_argument('--batch_size', type=int, default=4, help='Batch size')
-    parser.add_argument('--num_heads', type=int, default=6, help='Number of heads')
-    parser.add_argument('--head_dim', type=int, default=128, help='Head dimension')
-    parser.add_argument('--topk', type=int, default=4, help='Number of kv blocks each q block attends to')
-    parser.add_argument('--seq_lengths', type=int, nargs='+', default=[4096], help='Sequence lengths to benchmark')
-    parser.add_argument('--num_iterations', type=int, default=10, help='Number of test iterations to run')
-    args = parser.parse_args()
-    main(args)

csrc/attn/tests/test_full_attn.py

@@ -1,175 +0,0 @@
-import torch
-from flash_attn_interface import flash_attn_func
-from st_attn import mha_forward, mha_backward
-import random
-from tqdm import tqdm
-import matplotlib.pyplot as plt
-import numpy as np
-
-def pytorch_test(Q, K, V, dO):
-    q_ = Q.to(torch.float64).requires_grad_()
-    k_ = K.to(torch.float64).requires_grad_()
-    v_ = V.to(torch.float64).requires_grad_()
-    dO_ = dO.to(torch.float64)
-    
-    # manual pytorch implementation of scaled dot product attention
-    QK = torch.matmul(q_, k_.transpose(-2, -1))
-    QK /= (q_.size(-1) ** 0.5)
-    
-    # Causal mask removed since causal is always false
-    
-    QK = torch.nn.functional.softmax(QK, dim=-1)
-    output = torch.matmul(QK, v_)
-    
-    output.backward(dO_)
-    
-    q_grad = q_.grad
-    k_grad = k_.grad
-    v_grad = v_.grad
-    
-    return output, q_grad, k_grad, v_grad
-
-def fa2_test(Q, K, V, dO):
-    Q.requires_grad = True
-    K.requires_grad = True
-    V.requires_grad = True
-    output = torch.nn.functional.scaled_dot_product_attention(Q, K, V, is_causal=False)
-    output.backward(dO)
-    
-    return output, Q.grad, K.grad, V.grad
-
-
-def mha_kernel_test(Q, K, V, dO, mode): 
-    Q.requires_grad = True
-    K.requires_grad = True
-    V.requires_grad = True
-    
-    o, l_vec = mha_forward(Q, K, V)
-    
-    if mode == 'forward_only':
-        return o, None, None, None
-    else:  # 'forward_backward'
-        qg, kg, vg = mha_backward(Q, K, V, o, l_vec, dO)
-        return o, qg, kg, vg
-
-def generate_tensor(shape, mean, std, dtype, device):
-    tensor = torch.randn(shape, dtype=dtype, device=device)
-
-    magnitude = torch.norm(tensor, dim=-1, keepdim=True)
-    scaled_tensor = tensor * (torch.randn(magnitude.shape, dtype=dtype, device=device) * std + mean) / magnitude
-    
-    return scaled_tensor.contiguous()
-
-def check_correctness(b, h, n, d, mean, std, num_iterations=100, error_mode='all', test_mode='forward_backward'):
-    results = {
-        'MHA vs PT': {'sum_diff': 0, 'sum_abs': 0, 'max_diff': 0},
-        'FA2 vs PT': {'sum_diff': 0, 'sum_abs': 0, 'max_diff': 0},
-    }
-
-    for _ in range(num_iterations):
-        torch.manual_seed(0)
-        
-        Q  = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        K  = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        V  = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        dO = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        
-        pt_o, pt_qg, pt_kg, pt_vg = pytorch_test(Q, K, V, dO)
-        fa2_o, fa2_qg, fa2_kg, fa2_vg = fa2_test(Q, K, V, dO)
-        
-        if test_mode == 'forward_only':
-            mha_o, _, _, _ = mha_kernel_test(Q, K, V, dO, 'forward_only')
-            tensors_mha_pt = [(pt_o, mha_o)]
-            tensors_fa2_pt = [(pt_o, fa2_o)]
-        else:  # 'forward_backward'
-            mha_o, mha_qg, mha_kg, mha_vg = mha_kernel_test(Q, K, V, dO, 'forward_backward')
-            
-            if error_mode == 'output':
-                tensors_mha_pt = [(pt_o, mha_o)]
-                tensors_fa2_pt = [(pt_o, fa2_o)]
-            elif error_mode == 'backward':
-                tensors_mha_pt = [(pt_qg, mha_qg),
-                               (pt_kg, mha_kg),
-                               (pt_vg, mha_vg)]
-                tensors_fa2_pt = [(pt_qg, fa2_qg),
-                               (pt_kg, fa2_kg),
-                               (pt_vg, fa2_vg)]
-            else:  # 'all'
-                tensors_mha_pt = [(pt_o, mha_o),
-                               (pt_qg, mha_qg),
-                               (pt_kg, mha_kg),
-                               (pt_vg, mha_vg)]
-                tensors_fa2_pt = [(pt_o, fa2_o),
-                               (pt_qg, fa2_qg),
-                               (pt_kg, fa2_kg),
-                               (pt_vg, fa2_vg)]
-                
-        for pt, mha in tensors_mha_pt:
-            diff = pt - mha
-            abs_diff = torch.abs(diff)
-            results['MHA vs PT']['sum_diff'] += torch.sum(abs_diff).item()
-            results['MHA vs PT']['sum_abs'] += torch.sum(torch.abs(pt)).item()
-            results['MHA vs PT']['max_diff'] = max(results['MHA vs PT']['max_diff'], torch.max(abs_diff).item())
-                
-        for pt, fa2 in tensors_fa2_pt:
-            diff = pt - fa2
-            abs_diff = torch.abs(diff)
-            results['FA2 vs PT']['sum_diff'] += torch.sum(abs_diff).item()
-            results['FA2 vs PT']['sum_abs'] += torch.sum(torch.abs(pt)).item()
-            results['FA2 vs PT']['max_diff'] = max(results['FA2 vs PT']['max_diff'], torch.max(abs_diff).item())
-                
-        torch.cuda.empty_cache()
-
-    # Calculate total elements based on test mode and error mode
-    if test_mode == 'forward_only':
-        total_elements = b * h * n * d * num_iterations
-    else:  # 'forward_backward'
-        total_elements = b * h * n * d * num_iterations * (1 if error_mode == 'output' else 3 if error_mode == 'backward' else 4)
-    
-    for name, data in results.items():
-        avg_diff = data['sum_diff'] / total_elements
-        max_diff = data['max_diff']
-        results[name] = {'avg_diff': avg_diff, 'max_diff': max_diff}
-
-    return results
-
-def generate_error_tables(b, h, d, mean, std, error_mode='all', test_mode='forward_backward'):
-    seq_lengths = [768 * (2**i) for i in range(1)]
-
-    print(f"\n{'='*80}")
-    print(f"MHA ERROR COMPARISON TABLE (b={b}, h={h}, d={d}, mean={mean}, std={std})")
-    print(f"Mode: {error_mode}, Test: {test_mode}")
-    print(f"{'='*80}")
-    
-    # Print header
-    print(f"{'Seq Length':<12} | {'MHA vs PT Avg':<15} | {'MHA vs PT Max':<15} | {'FA2 vs PT Avg':<15} | {'FA2 vs PT Max':<15}")
-    print(f"{'-'*12} | {'-'*15} | {'-'*15} | {'-'*15} | {'-'*15}")
-    
-    for n in seq_lengths:
-        results = check_correctness(b, h, n, d, mean, std, error_mode=error_mode, test_mode=test_mode)
-        
-        mha_pt_avg = results['MHA vs PT']['avg_diff']
-        mha_pt_max = results['MHA vs PT']['max_diff']
-        fa2_pt_avg = results['FA2 vs PT']['avg_diff']
-        fa2_pt_max = results['FA2 vs PT']['max_diff']
-        
-        # Print row
-        print(f"{n:<12} | {mha_pt_avg:<15.6e} | {mha_pt_max:<15.6e} | {fa2_pt_avg:<15.6e} | {fa2_pt_max:<15.6e}")
-    
-    print(f"{'='*80}\n")
-
-# fix random seed
-torch.manual_seed(0)
-
-# Example usage
-b, h, d = 2, 2, 64
-mean = 1e-1
-std = 10
-
-# Test forward only
-generate_error_tables(b, h, d, mean, std, error_mode='output', test_mode='forward_only')
-
-# Test forward and backward
-generate_error_tables(b, h, d, mean, std, error_mode='all', test_mode='forward_backward')
-
-print("MHA attention error comparison completed.")

csrc/attn/tests/test_triton.py

@@ -1,183 +0,0 @@
-import torch
-from tqdm import tqdm
-import matplotlib.pyplot as plt
-import numpy as np
-
-from vsa import triton_attention
-
-def pytorch_test(Q, K, V, dO):
-    q_ = Q.to(torch.float64).requires_grad_()
-    k_ = K.to(torch.float64).requires_grad_()
-    v_ = V.to(torch.float64).requires_grad_()
-    q_.grad = None
-    k_.grad = None
-    v_.grad = None
-    dO_ = dO.to(torch.float64)
-    
-    # manual pytorch implementation of scaled dot product attention
-    QK = torch.matmul(q_, k_.transpose(-2, -1))
-    QK /= (q_.size(-1) ** 0.5)
-    
-    # Causal mask removed since causal is always false
-    
-    QK = torch.nn.functional.softmax(QK, dim=-1)
-    output = torch.matmul(QK, v_)
-    
-    output.backward(dO_)
-    
-    q_grad = q_.grad
-    k_grad = k_.grad
-    v_grad = v_.grad
-    
-    return output, q_grad, k_grad, v_grad
-
-def fa2_test(Q, K, V, dO):
-    Q.requires_grad = True
-    K.requires_grad = True
-    V.requires_grad = True
-    Q.grad = None
-    K.grad = None
-    V.grad = None
-    
-    output = torch.nn.functional.scaled_dot_product_attention(Q, K, V, is_causal=False)
-    output.backward(dO)
-    
-    return output, Q.grad, K.grad, V.grad
-
-def triton_test(Q, K, V, dO):
-    Q.requires_grad = True
-    K.requires_grad = True
-    V.requires_grad = True
-    Q.grad = None
-    K.grad = None
-    V.grad = None
-
-    output = triton_attention(Q, K, V)
-
-    output.backward(dO)
-    
-    q_grad = Q.grad
-    k_grad = K.grad
-    v_grad = V.grad
-    
-    return output.to(Q.dtype) if output is not None else None, q_grad, k_grad, v_grad
-
-def generate_tensor(shape, mean, std, dtype, device):
-    tensor = torch.randn(shape, dtype=dtype, device=device)
-
-    magnitude = torch.norm(tensor, dim=-1, keepdim=True)
-    scaled_tensor = tensor * (torch.randn(magnitude.shape, dtype=dtype, device=device) * std + mean) / magnitude
-    
-    return scaled_tensor.contiguous()
-
-def check_correctness(b, h, n, d, mean, std, num_iterations=100, error_mode='all', test_mode='forward_backward'):
-    results = {
-        'FA2 vs PT': {'sum_diff': 0.0, 'sum_abs': 0.0, 'max_diff': 0.0},
-        'Triton vs PT': {'sum_diff': 0.0, 'sum_abs': 0.0, 'max_diff': 0.0},
-    }
-
-    for _ in range(num_iterations):
-        torch.manual_seed(0)
-        
-        Q  = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        K  = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        V  = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        dO = generate_tensor((b, h, n, d), mean, std, torch.bfloat16, 'cuda')
-        
-        pt_o, pt_qg, pt_kg, pt_vg = pytorch_test(Q, K, V, dO)
-        fa2_o, fa2_qg, fa2_kg, fa2_vg = fa2_test(Q, K, V, dO)
-        triton_o, triton_qg, triton_kg, triton_vg = triton_test(Q, K, V, dO)
-        
-        if test_mode == 'forward_only':
-            tensors_fa2_pt = [(pt_o, fa2_o)]
-            tensors_triton_pt = [(pt_o, triton_o)]
-        else:  # 'forward_backward'
-            if error_mode == 'output':
-                tensors_fa2_pt = [(pt_o, fa2_o)]
-                tensors_triton_pt = [(pt_o, triton_o)]
-            elif error_mode == 'backward':
-                tensors_fa2_pt = [(pt_qg, fa2_qg),
-                               (pt_kg, fa2_kg),
-                               (pt_vg, fa2_vg)]
-                tensors_triton_pt = [(pt_qg, triton_qg),
-                                 (pt_kg, triton_kg),
-                                 (pt_vg, triton_vg)]
-            else:  # 'all'
-                tensors_fa2_pt = [(pt_o, fa2_o),
-                               (pt_qg, fa2_qg),
-                               (pt_kg, fa2_kg),
-                               (pt_vg, fa2_vg)]
-                tensors_triton_pt = [(pt_o, triton_o),
-                                 (pt_qg, triton_qg),
-                                 (pt_kg, triton_kg),
-                                 (pt_vg, triton_vg)]
-                
-        for pt, fa2 in tensors_fa2_pt:
-            diff = pt - fa2
-            abs_diff = torch.abs(diff)
-            results['FA2 vs PT']['sum_diff'] += torch.sum(abs_diff).item()
-            results['FA2 vs PT']['sum_abs'] += torch.sum(torch.abs(pt)).item()
-            results['FA2 vs PT']['max_diff'] = max(results['FA2 vs PT']['max_diff'], torch.max(abs_diff).item())
-        
-        for pt, triton in tensors_triton_pt:
-            diff = pt - triton
-            abs_diff = torch.abs(diff)
-            results['Triton vs PT']['sum_diff'] += torch.sum(abs_diff).item()
-            results['Triton vs PT']['sum_abs'] += torch.sum(torch.abs(pt)).item()
-            results['Triton vs PT']['max_diff'] = max(results['Triton vs PT']['max_diff'], torch.max(abs_diff).item())
-                
-        torch.cuda.empty_cache()
-
-    # Calculate total elements based on test mode and error mode
-    if test_mode == 'forward_only':
-        total_elements = b * h * n * d * num_iterations
-    else:  # 'forward_backward'
-        total_elements = b * h * n * d * num_iterations * (1 if error_mode == 'output' else 3 if error_mode == 'backward' else 4)
-    
-    for name, data in results.items():
-        avg_diff = data['sum_diff'] / total_elements
-        max_diff = data['max_diff']
-        results[name] = {'avg_diff': avg_diff, 'max_diff': max_diff}
-
-    return results
-
-def generate_error_tables(b, h, d, mean, std, error_mode='all', test_mode='forward_backward'):
-    seq_lengths = [768 * (2**i) for i in range(1)]
-
-    print(f"\n{'='*100}")
-    print(f"ATTENTION ERROR COMPARISON TABLE (b={b}, h={h}, d={d}, mean={mean}, std={std})")
-    print(f"Mode: {error_mode}, Test: {test_mode}")
-    print(f"{'='*100}")
-    
-    # Print header
-    print(f"{'Seq Length':<12} | {'FA2 vs PT Avg':<15} | {'FA2 vs PT Max':<15} | {'Triton vs PT Avg':<15} | {'Triton vs PT Max':<15}")
-    print(f"{'-'*12} | {'-'*15} | {'-'*15} | {'-'*15} | {'-'*15}")
-    
-    for n in seq_lengths:
-        results = check_correctness(b, h, n, d, mean, std, error_mode=error_mode, test_mode=test_mode)
-        
-        fa2_pt_avg = results['FA2 vs PT']['avg_diff']
-        fa2_pt_max = results['FA2 vs PT']['max_diff']
-        triton_pt_avg = results['Triton vs PT']['avg_diff']
-        triton_pt_max = results['Triton vs PT']['max_diff']
-        
-        # Print row with both comparisons
-        print(f"{n:<12} | {fa2_pt_avg:<15.6e} | {fa2_pt_max:<15.6e} | {triton_pt_avg:<15.6e} | {triton_pt_max:<15.6e}")
-    
-    print(f"{'='*100}\n")
-
-# fix random seed
-torch.manual_seed(0)
-
-mean = 1e-1
-std = 10
-configs = [
-    (4, 1, 128),  # Larger batch, single head, larger dim
-    (2, 8, 64),   # Medium batch, many heads, medium dim
-]
-
-for b, h, d in configs:
-    print(f"\nConfiguration: batch={b}, heads={h}, dim={d}")
-    generate_error_tables(b, h, d, mean, std, error_mode='backward', test_mode='forward_backward')
-
-print("Attention error comparison completed.")

csrc/attn/vsa.cpp

@@ -1,27 +0,0 @@
-#include <torch/extension.h>
-#include <ATen/ATen.h>
-
-#include <vector>
-#include <cuda_fp16.h>
-#include <cuda_bf16.h>
-
-#include <cuda_runtime.h>
-
-#ifdef TK_COMPILE_BLOCK_SPARSE
-extern std::vector<torch::Tensor> block_sparse_attention_forward(
-    torch::Tensor q, torch::Tensor k, torch::Tensor v,  torch::Tensor q2k_block_sparse_index, torch::Tensor q2k_block_sparse_num
-); 
-extern std::vector<torch::Tensor> block_sparse_attention_backward(
-    torch::Tensor q, torch::Tensor k, torch::Tensor v, torch::Tensor o, torch::Tensor l_vec, torch::Tensor og, torch::Tensor k2q_block_sparse_index, torch::Tensor k2q_block_sparse_num
-);
-#endif
-
-
-PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
-    m.doc() = "Video Sparse Attention Kernels"; // optional module docstring
-
-#ifdef TK_COMPILE_BLOCK_SPARSE
-    m.def("block_sparse_fwd",  torch::wrap_pybind_function(block_sparse_attention_forward), "block sparse attention");
-    m.def("block_sparse_bwd",  torch::wrap_pybind_function(block_sparse_attention_backward), "block sparse attention backward");
-#endif
-}

csrc/attn/vsa/__init__.py

@@ -1,278 +0,0 @@
-import torch
-from typing import Tuple
-from vsa.vsa import block_sparse_attn
-try:
-    from vsa_cuda import block_sparse_fwd, block_sparse_bwd
-except ImportError:
-    block_sparse_fwd = None
-    block_sparse_bwd = None
-from vsa.block_sparse_attn_triton import attention as triton_attention, attention_sparse as triton_attention_sparse
-BLOCK_M = 64
-BLOCK_N = 64
-
-
-def torch_attention(q, k, v) -> Tuple[torch.Tensor, torch.Tensor]:
-    QK = torch.matmul(q, k.transpose(-2, -1))
-    QK /= (q.size(-1)**0.5)
-
-    # Causal mask removed since causal is always false
-
-    QK = torch.nn.functional.softmax(QK, dim=-1)
-    output = torch.matmul(QK, v)
-    return output, QK
-
-
-def video_sparse_attn(q, k, v, topk, block_size, compress_attn_weight=None):
-    """
-    q: [batch_size, num_heads, seq_len, head_dim]
-    k: [batch_size, num_heads, seq_len, head_dim]
-    v: [batch_size, num_heads, seq_len, head_dim]
-    topk: int
-    block_size: int or tuple of 3 ints
-    video_shape: tuple of (T, H, W)
-    compress_attn_weight: [batch_size, num_heads, seq_len, head_dim]
-    select_attn_weight: [batch_size, num_heads, seq_len, head_dim]
-    
-    V1 of sparse attention. Include compress attn and sparse attn branch, use average pooling to compress. 
-    Assume q, k, v is flattened in this way: [batch_size, num_heads, T//block_size[0], H//block_size[1], W//block_size[2], block_size[0], block_size[1], block_size[2]]
-    """
-
-    if isinstance(block_size, int):
-        block_size = (block_size, block_size, block_size)
-
-    block_elements = block_size[0] * block_size[1] * block_size[2]
-    assert block_elements % 64 == 0 and block_elements >= 64
-    assert q.shape[2] % block_elements == 0
-    batch_size, num_heads, seq_len, head_dim = q.shape
-    # compress attn
-    q_compress = q.view(batch_size, num_heads, seq_len // block_elements,
-                        block_elements, head_dim).mean(dim=3)
-    k_compress = k.view(batch_size, num_heads, seq_len // block_elements,
-                        block_elements, head_dim).mean(dim=3)
-    v_compress = v.view(batch_size, num_heads, seq_len // block_elements,
-                        block_elements, head_dim).mean(dim=3)
-
-    output_compress, block_attn_score = torch_attention(q_compress, k_compress,
-                                                        v_compress)
-
-    output_compress = output_compress.view(batch_size, num_heads,
-                                           seq_len // block_elements, 1,
-                                           head_dim)
-    output_compress = output_compress.repeat(1, 1, 1, block_elements,
-                                             1).view(batch_size, num_heads,
-                                                     seq_len, head_dim)
-
-    q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num = generate_topk_block_sparse_pattern(
-        block_attn_score, topk)
-
-    output_select = block_sparse_attn(q, k, v, q2k_block_sparse_index,
-                                      q2k_block_sparse_num,
-                                      k2q_block_sparse_index,
-                                      k2q_block_sparse_num)
-
-    if compress_attn_weight is not None:
-        final_output = output_compress * compress_attn_weight + output_select
-    else:
-        final_output = output_compress + output_select
-    return final_output
-
-
-def generate_topk_block_sparse_pattern(block_attn_score: torch.Tensor,
-                                       topk: int):
-    """
-    Generate a block sparse pattern where each q block attends to exactly topk kv blocks,
-    based on the provided attention scores.
-    
-    Args:
-        block_attn_score: [bs, h, num_q_blocks, num_kv_blocks]
-            Attention scores between query and key blocks
-        topk: int
-            Number of kv blocks each q block attends to
-        
-    Returns:
-        q2k_block_sparse_index: [bs, h, num_q_blocks, topk]
-            Contains the indices of kv blocks that each q block attends to.
-        q2k_block_sparse_num: [bs, h, num_q_blocks]
-            Contains the number of kv blocks that each q block attends to (all equal to topk).
-        k2q_block_sparse_index: [bs, h, num_kv_blocks, max_q_per_kv]
-            Contains the indices of q blocks that attend to each kv block.
-        k2q_block_sparse_num: [bs, h, num_kv_blocks]
-            Contains the number of q blocks that attend to each kv block.
-    """
-    device = block_attn_score.device
-    # Extract dimensions from block_attn_score
-    bs, h, num_q_blocks, num_kv_blocks = block_attn_score.shape
-
-    sorted_result = torch.sort(block_attn_score, dim=-1, descending=True)
-
-    sorted_indice = sorted_result.indices
-
-    q2k_block_sparse_index, _ = torch.sort(sorted_indice[:, :, :, :topk],
-                                           dim=-1)
-    q2k_block_sparse_index = q2k_block_sparse_index.to(dtype=torch.int32)
-    q2k_block_sparse_num = torch.full((bs, h, num_q_blocks),
-                                      topk,
-                                      device=device,
-                                      dtype=torch.int32)
-
-    block_map = topk_index_to_map(q2k_block_sparse_index,
-                                  num_kv_blocks,
-                                  transpose_map=True)
-    k2q_block_sparse_index, k2q_block_sparse_num = map_to_index(
-        block_map.transpose(2, 3))
-
-    return q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num
-
-
-## pytorch sdpa version of block sparse ##
-import triton
-import triton.language as tl
-
-
-@triton.jit
-def topk_index_to_map_kernel(
-    map_ptr,
-    index_ptr,
-    map_bs_stride,
-    map_h_stride,
-    map_q_stride,
-    map_kv_stride,
-    index_bs_stride,
-    index_h_stride,
-    index_q_stride,
-    index_kv_stride,
-    topk: tl.constexpr,
-):
-    b, h, q = tl.program_id(0), tl.program_id(1), tl.program_id(2)
-    index_ptr_base = index_ptr + b * index_bs_stride + h * index_h_stride + q * index_q_stride
-    map_ptr_base = map_ptr + b * map_bs_stride + h * map_h_stride + q * map_q_stride
-
-    for i in tl.static_range(topk):
-        index = tl.load(index_ptr_base + i * index_kv_stride)
-        tl.store(map_ptr_base + index * map_kv_stride, 1.0)
-
-@triton.jit
-def map_to_index_kernel(
-    map_ptr,
-    index_ptr,
-    index_num_ptr,
-    map_bs_stride,
-    map_h_stride,
-    map_q_stride,
-    map_kv_stride,
-    index_bs_stride,
-    index_h_stride,
-    index_q_stride,
-    index_kv_stride,
-    index_num_bs_stride,
-    index_num_h_stride,
-    index_num_q_stride,
-    num_kv_blocks: tl.constexpr,
-):
-    b, h, q = tl.program_id(0), tl.program_id(1), tl.program_id(2)
-    index_ptr_base = index_ptr + b * index_bs_stride + h * index_h_stride + q * index_q_stride
-    map_ptr_base = map_ptr + b * map_bs_stride + h * map_h_stride + q * map_q_stride
-
-    num = 0
-    for i in tl.static_range(num_kv_blocks):
-        map_entry = tl.load(map_ptr_base + i * map_kv_stride)
-        if map_entry:
-            tl.store(index_ptr_base + num * index_kv_stride, i)
-            num += 1
-
-    tl.store(
-        index_num_ptr + b * index_num_bs_stride + h * index_num_h_stride +
-        q * index_num_q_stride, num)
-
-def topk_index_to_map(index: torch.Tensor,
-                      num_kv_blocks: int,
-                      transpose_map: bool = False):
-    """
-    Convert topk indices to a map.
-    
-    Args:
-        index: [bs, h, num_q_blocks, topk]
-            The topk indices tensor.
-        num_kv_blocks: int
-            The number of key-value blocks in the block_map returned
-        transpose_map: bool
-            If True, the block_map will be transposed on the final two dimensions.
-    
-    Returns:
-        block_map: [bs, h, num_q_blocks, num_kv_blocks]
-            A binary map where 1 indicates that the q block attends to the kv block.
-    """
-    bs, h, num_q_blocks, topk = index.shape
-
-    if transpose_map is False:
-        block_map = torch.zeros((bs, h, num_q_blocks, num_kv_blocks),
-                                dtype=torch.bool,
-                                device=index.device)
-    else:
-        block_map = torch.zeros((bs, h, num_kv_blocks, num_q_blocks),
-                                dtype=torch.bool,
-                                device=index.device)
-        block_map = block_map.transpose(2, 3)
-
-    grid = (bs, h, num_q_blocks)
-    topk_index_to_map_kernel[grid](
-        block_map,
-        index,
-        block_map.stride(0),
-        block_map.stride(1),
-        block_map.stride(2),
-        block_map.stride(3),
-        index.stride(0),
-        index.stride(1),
-        index.stride(2),
-        index.stride(3),
-        topk=topk,
-    )
-
-    return block_map
-
-def map_to_index(block_map: torch.Tensor):
-    """
-    Convert a block map to indices and counts.
-    
-    Args:
-        block_map: [bs, h, num_q_blocks, num_kv_blocks]
-            The block map tensor.
-    
-    Returns:
-        index: [bs, h, num_q_blocks, num_kv_blocks]
-            The indices of the blocks.
-        index_num: [bs, h, num_q_blocks]
-            The number of blocks for each q block.
-    """
-    bs, h, num_q_blocks, num_kv_blocks = block_map.shape
-
-    index = torch.full((block_map.shape),
-                       -1,
-                       dtype=torch.int32,
-                       device=block_map.device)
-    index_num = torch.empty((bs, h, num_q_blocks),
-                            dtype=torch.int32,
-                            device=block_map.device)
-
-    grid = (bs, h, num_q_blocks)
-    map_to_index_kernel[grid](
-        block_map,
-        index,
-        index_num,
-        block_map.stride(0),
-        block_map.stride(1),
-        block_map.stride(2),
-        block_map.stride(3),
-        index.stride(0),
-        index.stride(1),
-        index.stride(2),
-        index.stride(3),
-        index_num.stride(0),
-        index_num.stride(1),
-        index_num.stride(2),
-        num_kv_blocks=num_kv_blocks,
-    )
-
-    return index, index_num
-

csrc/attn/vsa/block_sparse_attn_triton.py

@@ -1,707 +0,0 @@
-"""
-Fused Attention
-===============
-
-This is a Triton implementation of the Flash Attention v2 algorithm from Tri Dao
-(https://tridao.me/publications/flash2/flash2.pdf)
-
-Credits: OpenAI kernel team
-"""
-
-import pytest
-import torch
-import triton
-import triton.language as tl
-
-# ──────────────────────────── SPARSE ADDITION BEGIN ───────────────────────────
-import math  # small utility needed by the sparse wrapper
-# ──────────────────────────── SPARSE ADDITION END ─────────────────────────────
-
-
-@triton.jit
-def _attn_fwd_inner(acc, l_i, m_i, q,  #
-                    K_block_ptr, V_block_ptr,  #
-                    start_m, qk_scale,  #
-                    BLOCK_M: tl.constexpr, HEAD_DIM: tl.constexpr, BLOCK_N: tl.constexpr,  #
-                    STAGE: tl.constexpr, offs_m: tl.constexpr, offs_n: tl.constexpr,  #
-                    N_CTX: tl.constexpr, fp8_v: tl.constexpr):
-
-    # loop over k, v and update accumulator
-    for start_n in range(0, N_CTX, BLOCK_N):
-        # -- compute qk ----
-        k = tl.load(K_block_ptr)
-        qk = tl.dot(q, k)
-
-        m_ij = tl.maximum(m_i, tl.max(qk, 1) * qk_scale)
-        qk = qk * qk_scale - m_ij[:, None]
-        p = tl.math.exp2(qk)
-        l_ij = tl.sum(p, 1)
-        # -- update m_i and l_i
-        alpha = tl.math.exp2(m_i - m_ij)
-        l_i = l_i * alpha + l_ij
-        # -- update output accumulator --
-        acc = acc * alpha[:, None]
-        # update acc
-        v = tl.load(V_block_ptr)
-        if fp8_v:
-            p = p.to(tl.float8e5)
-        else:
-            p = p.to(tl.bfloat16)
-        acc = tl.dot(p, v, acc)
-        # update m_i and l_i
-        m_i = m_ij
-        V_block_ptr = tl.advance(V_block_ptr, (BLOCK_N, 0))
-        K_block_ptr = tl.advance(K_block_ptr, (0, BLOCK_N))
-    return acc, l_i, m_i
-
-
-# We don't run auto-tuning every time to keep the tutorial fast. Keeping
-# the code below and commenting out the equivalent parameters is convenient for
-# re-tuning.
-configs = [
-    triton.Config({'BLOCK_M': BM, 'BLOCK_N': BN}, num_stages=s, num_warps=w) \
-    for BM in [64]\
-    for BN in [64]\
-    for s in [3, 4, 7]\
-    for w in [4, 8]\
-]
-
-# ──────────────────────────── SPARSE ADDITION BEGIN ───────────────────────────
-@triton.autotune(configs, key=["N_CTX", "HEAD_DIM"])
-@triton.jit
-def _attn_fwd_sparse(Q, K, V, sm_scale,                         #
-                     q2k_index, q2k_num, max_kv_blks,           #
-                     M, Out,                                    #
-                     stride_qz, stride_qh, stride_qm, stride_qk,
-                     stride_kz, stride_kh, stride_kn, stride_kk,
-                     stride_vz, stride_vh, stride_vk, stride_vn,
-                     stride_oz, stride_oh, stride_om, stride_on,
-                     Z, H, N_CTX,                               #
-                     HEAD_DIM: tl.constexpr,                    #
-                     BLOCK_M: tl.constexpr, BLOCK_N: tl.constexpr,
-                     STAGE: tl.constexpr):
-    """
-    64×64 **block-sparse** forward kernel. Back-prop kernels remain dense
-    (32×64 and 64×32) – memory footprint unchanged.
-    """
-
-    # ----- program-id mapping -----
-    q_blk   = tl.program_id(0)          # Q-tile index
-    off_hz  = tl.program_id(1)          # fused (batch, head)
-    b       = off_hz // H
-    h       = off_hz %  H
-    q_tiles = N_CTX // BLOCK_M
-    meta_base = ((b * H + h) * q_tiles + q_blk)
-
-    kv_blocks = tl.load(q2k_num  + meta_base)                 # int32
-    kv_ptr    = q2k_index + meta_base * max_kv_blks           # ptr to list
-
-    # ----- base pointers -----
-    qvk_off = (b.to(tl.int64) * stride_qz +
-               h.to(tl.int64) * stride_qh)
-
-    Q_ptr = tl.make_block_ptr(
-        base=Q + qvk_off, shape=(N_CTX, HEAD_DIM),
-        strides=(stride_qm, stride_qk),
-        offsets=(q_blk * BLOCK_M, 0),
-        block_shape=(BLOCK_M, HEAD_DIM), order=(1, 0))
-
-    K_base = tl.make_block_ptr(
-        base=K + qvk_off, shape=(HEAD_DIM, N_CTX),
-        strides=(stride_kk, stride_kn),
-        offsets=(0, 0),
-        block_shape=(HEAD_DIM, BLOCK_N), order=(0, 1))
-
-    v_order: tl.constexpr = (0, 1) if V.dtype.element_ty == tl.float8e5 else (1, 0)
-    V_base = tl.make_block_ptr(
-        base=V + qvk_off, shape=(N_CTX, HEAD_DIM),
-        strides=(stride_vk, stride_vn),
-        offsets=(0, 0),
-        block_shape=(BLOCK_N, HEAD_DIM), order=v_order)
-
-    O_ptr = tl.make_block_ptr(
-        base=Out + qvk_off, shape=(N_CTX, HEAD_DIM),
-        strides=(stride_om, stride_on),
-        offsets=(q_blk * BLOCK_M, 0),
-        block_shape=(BLOCK_M, HEAD_DIM), order=(1, 0))
-
-    # ----- accumulators -----
-    offs_m = q_blk * BLOCK_M + tl.arange(0, BLOCK_M)
-    m_i = tl.full([BLOCK_M], -float("inf"), tl.float32)
-    l_i = tl.zeros([BLOCK_M], dtype=tl.float32) + 1.0
-    acc = tl.zeros([BLOCK_M, HEAD_DIM], dtype=tl.float32)
-    qk_scale = sm_scale * 1.44269504  # 1/ln2
-    q = tl.load(Q_ptr)
-
-    # ----- sparse loop over valid K/V tiles -----
-    for i in range(0, kv_blocks):
-        kv_idx = tl.load(kv_ptr + i).to(tl.int32)
-
-        K_ptr = tl.advance(K_base, (0, kv_idx * BLOCK_N))
-        V_ptr = tl.advance(V_base, (kv_idx * BLOCK_N, 0))
-
-        k = tl.load(K_ptr)
-        qk = tl.dot(q, k)
-
-        m_ij = tl.maximum(m_i, tl.max(qk, 1) * qk_scale)
-        p = tl.math.exp2(qk * qk_scale - m_ij[:, None])
-        l_ij = tl.sum(p, 1)
-
-        alpha = tl.math.exp2(m_i - m_ij)
-        l_i = l_i * alpha + l_ij
-        acc = acc * alpha[:, None]
-
-        v = tl.load(V_ptr)
-        acc = tl.dot(p.to(tl.bfloat16), v, acc)
-        m_i = m_ij
-
-    # ----- epilogue -----
-    m_i += tl.math.log2(l_i)
-    acc = acc / l_i[:, None]
-    tl.store(M + off_hz * N_CTX + offs_m, m_i)
-    tl.store(O_ptr, acc.to(Out.type.element_ty))
-# ──────────────────────────── SPARSE ADDITION END ─────────────────────────────
-
-
-@triton.autotune(configs, key=["N_CTX", "HEAD_DIM"])
-@triton.jit
-def _attn_fwd(Q, K, V, sm_scale, M, Out,  #
-              stride_qz, stride_qh, stride_qm, stride_qk,  #
-              stride_kz, stride_kh, stride_kn, stride_kk,  #
-              stride_vz, stride_vh, stride_vk, stride_vn,  #
-              stride_oz, stride_oh, stride_om, stride_on,  #
-              Z, H, N_CTX,  #
-              HEAD_DIM: tl.constexpr,  #
-              BLOCK_M: tl.constexpr,  #
-              BLOCK_N: tl.constexpr,  #
-              STAGE: tl.constexpr  #
-              ):
-    tl.static_assert(BLOCK_N <= HEAD_DIM)
-    start_m = tl.program_id(0)
-    off_hz = tl.program_id(1)
-    off_z = off_hz // H
-    off_h = off_hz % H
-    qvk_offset = off_z.to(tl.int64) * stride_qz + off_h.to(tl.int64) * stride_qh
-
-    # block pointers
-    Q_block_ptr = tl.make_block_ptr(
-        base=Q + qvk_offset,
-        shape=(N_CTX, HEAD_DIM),
-        strides=(stride_qm, stride_qk),
-        offsets=(start_m * BLOCK_M, 0),
-        block_shape=(BLOCK_M, HEAD_DIM),
-        order=(1, 0),
-    )
-    v_order: tl.constexpr = (0, 1) if V.dtype.element_ty == tl.float8e5 else (1, 0)
-    V_block_ptr = tl.make_block_ptr(
-        base=V + qvk_offset,
-        shape=(N_CTX, HEAD_DIM),
-        strides=(stride_vk, stride_vn),
-        offsets=(0, 0),
-        block_shape=(BLOCK_N, HEAD_DIM),
-        order=v_order,
-    )
-    K_block_ptr = tl.make_block_ptr(
-        base=K + qvk_offset,
-        shape=(HEAD_DIM, N_CTX),
-        strides=(stride_kk, stride_kn),
-        offsets=(0, 0),
-        block_shape=(HEAD_DIM, BLOCK_N),
-        order=(0, 1),
-    )
-    O_block_ptr = tl.make_block_ptr(
-        base=Out + qvk_offset,
-        shape=(N_CTX, HEAD_DIM),
-        strides=(stride_om, stride_on),
-        offsets=(start_m * BLOCK_M, 0),
-        block_shape=(BLOCK_M, HEAD_DIM),
-        order=(1, 0),
-    )
-    # initialize offsets
-    offs_m = start_m * BLOCK_M + tl.arange(0, BLOCK_M)
-    offs_n = tl.arange(0, BLOCK_N)
-    # initialize pointer to m and l
-    m_i = tl.zeros([BLOCK_M], dtype=tl.float32) - float("inf")
-    l_i = tl.zeros([BLOCK_M], dtype=tl.float32) + 1.0
-    acc = tl.zeros([BLOCK_M, HEAD_DIM], dtype=tl.float32)
-    # load scales
-    qk_scale = sm_scale
-    qk_scale *= 1.44269504  # 1/log(2)
-    # load q: it will stay in SRAM throughout
-    q = tl.load(Q_block_ptr)
-    acc, l_i, m_i = _attn_fwd_inner(acc, l_i, m_i, q, K_block_ptr, V_block_ptr,  #
-                                    start_m, qk_scale,  #
-                                    BLOCK_M, HEAD_DIM, BLOCK_N,  #
-                                    3, offs_m, offs_n, N_CTX, V.dtype.element_ty == tl.float8e5  #
-                                    )
-
-    # epilogue
-    m_i += tl.math.log2(l_i)
-    acc = acc / l_i[:, None]
-    m_ptrs = M + off_hz * N_CTX + offs_m
-    tl.store(m_ptrs, m_i)
-    tl.store(O_block_ptr, acc.to(Out.type.element_ty))
-
-
-@triton.jit
-def _attn_bwd_preprocess(O, DO,  #
-                         Delta,  #
-                         Z, H, N_CTX,  #
-                         BLOCK_M: tl.constexpr, HEAD_DIM: tl.constexpr  #
-                         ):
-    off_m = tl.program_id(0) * BLOCK_M + tl.arange(0, BLOCK_M)
-    off_hz = tl.program_id(1)
-    off_n = tl.arange(0, HEAD_DIM)
-    # load
-    o = tl.load(O + off_hz * HEAD_DIM * N_CTX + off_m[:, None] * HEAD_DIM + off_n[None, :])
-    do = tl.load(DO + off_hz * HEAD_DIM * N_CTX + off_m[:, None] * HEAD_DIM + off_n[None, :]).to(tl.float32)
-    delta = tl.sum(o * do, axis=1)
-    # write-back
-    tl.store(Delta + off_hz * N_CTX + off_m, delta)
-
-
-# The main inner-loop logic for computing dK and dV.
-@triton.jit
-def _attn_bwd_dkdv(dk, dv,  #
-                   Q, k, v, sm_scale,  #
-                   DO,  #
-                   M, D,  #
-                   k2q_index, k2q_num, max_q_blks,
-                   # shared by Q/K/V/DO.
-                   stride_tok, stride_d,  #
-                   H, N_CTX, BLOCK_M1: tl.constexpr,  #
-                   BLOCK_N1: tl.constexpr,  #
-                   HEAD_DIM: tl.constexpr,  #
-                   # Filled in by the wrapper.
-                   start_n, start_m, num_steps):
-    offs_m = start_m + tl.arange(0, BLOCK_M1)
-    offs_n = start_n + tl.arange(0, BLOCK_N1)
-    offs_k = tl.arange(0, HEAD_DIM)
-    qT_ptrs = Q + offs_m[None, :] * stride_tok + offs_k[:, None] * stride_d
-    do_ptrs = DO + offs_m[:, None] * stride_tok + offs_k[None, :] * stride_d
-    # BLOCK_N1 must be a multiple of BLOCK_M1, otherwise the code wouldn't work.
-    tl.static_assert(BLOCK_N1 % BLOCK_M1 == 0)
-    step_m = BLOCK_M1
-    kv_blk   = tl.program_id(0)          # Q-tile index
-    off_hz  = tl.program_id(2)          # fused (batch, head)
-    b       = off_hz // H
-    h       = off_hz %  H
-    q_tiles = N_CTX // BLOCK_N1
-    meta_base = ((b * H + h) * q_tiles + kv_blk)
-
-    q_blocks = tl.load(k2q_num  + meta_base)                 # int32
-    q_ptr    = k2q_index + meta_base * max_q_blks           # ptr to list
-    
-        
-    for blk_idx in range(q_blocks*2):
-        block_sparse_offset = (tl.load(q_ptr + blk_idx//2).to(tl.int32)*2 + blk_idx%2) *step_m
-        qT = tl.load(qT_ptrs + block_sparse_offset * stride_tok)
-        # Load m before computing qk to reduce pipeline stall.
-        offs_m = start_m + block_sparse_offset + tl.arange(0, BLOCK_M1)
-        m = tl.load(M + offs_m)
-        qkT = tl.dot(k, qT)
-        pT = tl.math.exp2(qkT - m[None, :])
-        do = tl.load(do_ptrs + block_sparse_offset * stride_tok)
-        # Compute dV.
-        ppT = pT
-        ppT = ppT.to(tl.bfloat16)
-        dv += tl.dot(ppT, do)
-        # D (= delta) is pre-divided by ds_scale.
-        Di = tl.load(D + offs_m)
-        # Compute dP and dS.
-        dpT = tl.dot(v, tl.trans(do)).to(tl.float32)
-        dsT = pT * (dpT - Di[None, :])
-        dsT = dsT.to(tl.bfloat16)
-        dk += tl.dot(dsT, tl.trans(qT))
-        # Increment pointers.
-    return dk, dv
-
-
-
-# the main inner-loop logic for computing dQ
-@triton.jit
-def _attn_bwd_dq(dq, q, K, V,  #
-                 do, m, D,
-                 # shared by Q/K/V/DO.
-                 q2k_index, q2k_num, max_kv_blks,
-                 stride_tok, stride_d,  #
-                 H, N_CTX,  #
-                 BLOCK_M2: tl.constexpr,  #
-                 BLOCK_N2: tl.constexpr,  #
-                 HEAD_DIM: tl.constexpr,
-                 # Filled in by the wrapper.
-                 start_m, start_n, num_steps):
-    offs_m = start_m + tl.arange(0, BLOCK_M2)
-    offs_n = start_n + tl.arange(0, BLOCK_N2)
-    offs_k = tl.arange(0, HEAD_DIM)
-    kT_ptrs = K + offs_n[None, :] * stride_tok + offs_k[:, None] * stride_d
-    vT_ptrs = V + offs_n[None, :] * stride_tok + offs_k[:, None] * stride_d
-    # D (= delta) is pre-divided by ds_scale.
-    Di = tl.load(D + offs_m)
-    # BLOCK_M2 must be a multiple of BLOCK_N2, otherwise the code wouldn't work.
-    tl.static_assert(BLOCK_M2 % BLOCK_N2 == 0)
-    step_n = BLOCK_N2
-    
-    q_blk   = tl.program_id(0)          # Q-tile index
-    off_hz  = tl.program_id(2)          # fused (batch, head)
-    b       = off_hz // H
-    h       = off_hz %  H
-    q_tiles = N_CTX // BLOCK_M2
-    meta_base = ((b * H + h) * q_tiles + q_blk)
-
-    kv_blocks = tl.load(q2k_num  + meta_base)                 # int32
-    kv_ptr    = q2k_index + meta_base * max_kv_blks           # ptr to list
-    
-    
-    for blk_idx in range(kv_blocks*2):
-        block_sparse_offset = (tl.load(kv_ptr + blk_idx//2).to(tl.int32)*2 + blk_idx%2) *step_n * stride_tok
-        kT = tl.load(kT_ptrs + block_sparse_offset)
-        vT = tl.load(vT_ptrs + block_sparse_offset)
-        qk = tl.dot(q, kT)
-        p = tl.math.exp2(qk - m)
-        # Compute dP and dS.
-        dp = tl.dot(do, vT).to(tl.float32)
-        ds = p * (dp - Di[:, None])
-        ds = ds.to(tl.bfloat16)
-        # Compute dQ.
-        # NOTE: We need to de-scale dq in the end, because kT was pre-scaled.
-        dq += tl.dot(ds, tl.trans(kT))
-        # Increment pointers.
-    return dq
-
-
-
-@triton.jit
-def _attn_bwd(Q, K, V, sm_scale,  #
-              DO,  #
-              DQ, DK, DV,  #
-              M, D,
-              q2k_index, q2k_num, max_kv_blks,
-              k2q_index, k2q_num, max_q_blks,
-              # shared by Q/K/V/DO.
-              stride_z, stride_h, stride_tok, stride_d,  #
-              H, N_CTX,  #
-              BLOCK_M1: tl.constexpr,  #
-              BLOCK_N1: tl.constexpr,  #
-              BLOCK_M2: tl.constexpr,  #
-              BLOCK_N2: tl.constexpr,  #
-              HEAD_DIM: tl.constexpr):
-    LN2 = 0.6931471824645996  # = ln(2)
-
-    bhid = tl.program_id(2)
-    off_chz = (bhid * N_CTX).to(tl.int64)
-    adj = (stride_h * (bhid % H) + stride_z * (bhid // H)).to(tl.int64)
-    pid = tl.program_id(0)
-
-    # offset pointers for batch/head
-    Q += adj
-    K += adj
-    V += adj
-    DO += adj
-    DQ += adj
-    DK += adj
-    DV += adj
-    M += off_chz
-    D += off_chz
-
-    # load scales
-    offs_k = tl.arange(0, HEAD_DIM)
-
-    start_n = pid * BLOCK_N1
-    start_m = 0
-
-    offs_n = start_n + tl.arange(0, BLOCK_N1)
-
-    dv = tl.zeros([BLOCK_N1, HEAD_DIM], dtype=tl.float32)
-    dk = tl.zeros([BLOCK_N1, HEAD_DIM], dtype=tl.float32)
-
-    # load K and V: they stay in SRAM throughout the inner loop.
-    k = tl.load(K + offs_n[:, None] * stride_tok + offs_k[None, :] * stride_d)
-    v = tl.load(V + offs_n[:, None] * stride_tok + offs_k[None, :] * stride_d)
-
-
-    num_steps = N_CTX // BLOCK_M1
-
-    dk, dv = _attn_bwd_dkdv(  #
-        dk, dv,  #
-        Q, k, v, sm_scale,  #
-        DO,  #
-        M, D,  #
-        k2q_index, k2q_num, max_q_blks,
-        stride_tok, stride_d,  #
-        H, N_CTX,  #
-        BLOCK_M1, BLOCK_N1, HEAD_DIM,  #
-        start_n, start_m, num_steps  #
-    )
-
-    dv_ptrs = DV + offs_n[:, None] * stride_tok + offs_k[None, :] * stride_d
-    tl.store(dv_ptrs, dv)
-
-    # Write back dK.
-    dk *= sm_scale
-    dk_ptrs = DK + offs_n[:, None] * stride_tok + offs_k[None, :] * stride_d
-    tl.store(dk_ptrs, dk)
-
-    # THIS BLOCK DOES DQ:
-    start_m = pid * BLOCK_M2
-    end_n = 0
-
-    offs_m = start_m + tl.arange(0, BLOCK_M2)
-
-    q = tl.load(Q + offs_m[:, None] * stride_tok + offs_k[None, :] * stride_d)
-    dq = tl.zeros([BLOCK_M2, HEAD_DIM], dtype=tl.float32)
-    do = tl.load(DO + offs_m[:, None] * stride_tok + offs_k[None, :] * stride_d)
-
-    m = tl.load(M + offs_m)
-    m = m[:, None]
-
-    num_steps = N_CTX // BLOCK_N2
-    dq = _attn_bwd_dq(dq, q, K, V,  #
-                      do, m, D,  #
-                      q2k_index, q2k_num, max_kv_blks,
-                      stride_tok, stride_d,  #
-                      H, N_CTX,  #
-                      BLOCK_M2, BLOCK_N2, HEAD_DIM,  #
-                      start_m, end_n, num_steps  #
-                      )
-    # Write back dQ.
-    dq_ptrs = DQ + offs_m[:, None] * stride_tok + offs_k[None, :] * stride_d
-    dq *= LN2
-    tl.store(dq_ptrs, dq)
-    
-    
-
-class _attention(torch.autograd.Function):
-
-    @staticmethod
-    def forward(ctx, q, k, v):
-        # shape constraints
-        sm_scale = 1.0 / (q.shape[-1] ** 0.5)
-        HEAD_DIM_Q, HEAD_DIM_K = q.shape[-1], k.shape[-1]
-        # when v is in float8_e5m2 it is transposed.
-        HEAD_DIM_V = v.shape[-1]
-        assert HEAD_DIM_Q == HEAD_DIM_K and HEAD_DIM_K == HEAD_DIM_V
-        assert HEAD_DIM_K in {16, 32, 64, 128, 256}
-        o = torch.empty_like(q)
-        stage = 1
-        extra_kern_args = {}
-
-
-        grid = lambda args: (triton.cdiv(q.shape[2], args["BLOCK_M"]), q.shape[0] * q.shape[1], 1)
-        M = torch.empty((q.shape[0], q.shape[1], q.shape[2]), device=q.device, dtype=torch.float32)
-        _attn_fwd[grid](
-            q, k, v, sm_scale, M, o,  #
-            q.stride(0), q.stride(1), q.stride(2), q.stride(3),  #
-            k.stride(0), k.stride(1), k.stride(2), k.stride(3),  #
-            v.stride(0), v.stride(1), v.stride(2), v.stride(3),  #
-            o.stride(0), o.stride(1), o.stride(2), o.stride(3),  #
-            q.shape[0], q.shape[1],  #
-            N_CTX=q.shape[2],  #
-            HEAD_DIM=HEAD_DIM_K,  #
-            STAGE=stage,  #
-            **extra_kern_args)
-
-        ctx.save_for_backward(q, k, v, o, M)
-        ctx.grid = grid
-        ctx.sm_scale = sm_scale
-        ctx.HEAD_DIM = HEAD_DIM_K
-        return o
-
-    @staticmethod
-    def backward(ctx, do):
-        q, k, v, o, M = ctx.saved_tensors
-        assert do.is_contiguous()
-        assert q.stride() == k.stride() == v.stride() == o.stride() == do.stride()
-        dq = torch.empty_like(q)
-        dk = torch.empty_like(k)
-        dv = torch.empty_like(v)
-        BATCH, N_HEAD, N_CTX = q.shape[:3]
-        PRE_BLOCK = 128
-        BLOCK_M1, BLOCK_N1, BLOCK_M2, BLOCK_N2 = 32, 64, 64, 32
-        RCP_LN2 = 1.4426950408889634  # = 1.0 / ln(2)
-        arg_k = k
-        arg_k = arg_k * (ctx.sm_scale * RCP_LN2)
-        PRE_BLOCK = 128
-        assert N_CTX % PRE_BLOCK == 0
-        pre_grid = (N_CTX // PRE_BLOCK, BATCH * N_HEAD)
-        delta = torch.empty_like(M)
-        _attn_bwd_preprocess[pre_grid](
-            o, do,  #
-            delta,  #
-            BATCH, N_HEAD, N_CTX,  #
-            BLOCK_M=PRE_BLOCK, HEAD_DIM=ctx.HEAD_DIM  #
-        )
-        grid = (N_CTX // BLOCK_N1, 1, BATCH * N_HEAD)
-        _attn_bwd[grid](
-            q, arg_k, v, ctx.sm_scale, do, dq, dk, dv,  #
-            M, delta,  #
-            q.stride(0), q.stride(1), q.stride(2), q.stride(3),  #
-            N_HEAD, N_CTX,  #
-            BLOCK_M1=BLOCK_M1, BLOCK_N1=BLOCK_N1,  #
-            BLOCK_M2=BLOCK_M2, BLOCK_N2=BLOCK_N2,  #
-            HEAD_DIM=ctx.HEAD_DIM  #
-        )
-
-        return dq, dk, dv, None, None
-
-
-attention = _attention.apply
-
-# ──────────────────────────── SPARSE ADDITION BEGIN ───────────────────────────
-class _attention_sparse(torch.autograd.Function):
-    """
-    Thin autograd wrapper that uses the sparse forward kernel above and the
-    standard dense backward kernels defined earlier (no extra memory use).
-    """
-
-    @staticmethod
-    def forward(ctx, q, k, v, q2k_index, q2k_num, k2q_index, k2q_num):
-        B, H, T, D = q.shape
-        sm_scale = 1.0 / math.sqrt(D)
-        max_kv_blks = q2k_index.shape[-1]
-        assert T % 64 == 0, f"T must be a multiple of 64, but got {T}"
-        assert T // 64 == q2k_num.shape[-1], f"shape mismatch, T // 64 = {T // 64}, q2k_num.shape[-2] = {q2k_num.shape[-2]}"
-        o = torch.empty_like(q)
-        M = torch.empty((B, H, T), dtype=torch.float32, device=q.device)
-
-        grid = lambda _: (triton.cdiv(T, 64), B * H, 1)
-        _attn_fwd_sparse[grid](
-            q, k, v, sm_scale,
-            q2k_index, q2k_num, max_kv_blks,
-            M, o,
-            q.stride(0), q.stride(1), q.stride(2), q.stride(3),
-            k.stride(0), k.stride(1), k.stride(2), k.stride(3),
-            v.stride(0), v.stride(1), v.stride(2), v.stride(3),
-            o.stride(0), o.stride(1), o.stride(2), o.stride(3),
-            B, H, T,
-            HEAD_DIM=D, STAGE=3
-        )
-
-        ctx.save_for_backward(q, k, v, o, M, q2k_index, q2k_num, k2q_index, k2q_num)
-        ctx.grid = None
-        ctx.sm_scale = sm_scale
-        ctx.HEAD_DIM = D
-        return o
-
-    @staticmethod
-    def backward(ctx, do):
-        q, k, v, o, M, q2k_index, q2k_num, k2q_index, k2q_num = ctx.saved_tensors
-        assert do.is_contiguous()
-        assert q.stride() == k.stride() == v.stride() == o.stride() == do.stride()
-        dq = torch.empty_like(q)
-        dk = torch.empty_like(k)
-        dv = torch.empty_like(v)
-        BATCH, N_HEAD, N_CTX = q.shape[:3]
-        PRE_BLOCK = 128
-        BLOCK_M1, BLOCK_N1, BLOCK_M2, BLOCK_N2 = 32, 64, 64, 32
-        RCP_LN2 = 1.4426950408889634  # = 1.0 / ln(2)
-        arg_k = k
-        arg_k = arg_k * (ctx.sm_scale * RCP_LN2)
-        PRE_BLOCK = 128
-        assert N_CTX % PRE_BLOCK == 0
-        pre_grid = (N_CTX // PRE_BLOCK, BATCH * N_HEAD)
-        delta = torch.empty_like(M)
-        _attn_bwd_preprocess[pre_grid](
-            o, do,  #
-            delta,  #
-            BATCH, N_HEAD, N_CTX,  #
-            BLOCK_M=PRE_BLOCK, HEAD_DIM=ctx.HEAD_DIM  #
-        )
-        
-        
-        max_q_blks = k2q_index.shape[-1]
-        max_kv_blks = q2k_index.shape[-1]
-        
-        
-        grid = (N_CTX // BLOCK_N1, 1, BATCH * N_HEAD)
-        _attn_bwd[grid](
-            q, arg_k, v, ctx.sm_scale, do, dq, dk, dv,  #
-            M, delta,  #
-            q2k_index, q2k_num, max_kv_blks,
-            k2q_index, k2q_num, max_q_blks,
-            q.stride(0), q.stride(1), q.stride(2), q.stride(3),  #
-            N_HEAD, N_CTX,  #
-            BLOCK_M1=BLOCK_M1, BLOCK_N1=BLOCK_N1,  #
-            BLOCK_M2=BLOCK_M2, BLOCK_N2=BLOCK_N2,  #
-            HEAD_DIM=ctx.HEAD_DIM  #
-        )
-
-        return dq, dk, dv, None, None, None, None
-
-attention_sparse = _attention_sparse.apply
-# ──────────────────────────── SPARSE ADDITION END ─────────────────────────────
-
-
-try:
-    from flash_attn.flash_attn_interface import \
-        flash_attn_qkvpacked_func as flash_attn_func
-    HAS_FLASH = True
-except BaseException:
-    HAS_FLASH = False
-
-TORCH_HAS_FP8 = hasattr(torch, 'float8_e5m2')
-BATCH, N_HEADS, HEAD_DIM = 4, 32, 128
-# vary seq length for fixed head and batch=4
-configs = []
-for mode in ["fwd", "bwd"]:
-        configs.append(
-            triton.testing.Benchmark(
-                x_names=["N_CTX"],
-                x_vals=[2**i for i in range(10, 15)],
-                line_arg="provider",
-                line_vals=["triton-fp16"] + (["triton-fp8"] if TORCH_HAS_FP8 else []) +
-                (["flash"] if HAS_FLASH else []),
-                line_names=["Triton [FP16]"] + (["Triton [FP8]"] if TORCH_HAS_FP8 else []) +
-                (["Flash-2"] if HAS_FLASH else []),
-                styles=[("red", "-"), ("blue", "-"), ("green", "-")],
-                ylabel="ms",
-                plot_name=f"fused-attention-batch{BATCH}-head{N_HEADS}-d{HEAD_DIM}-{mode}",
-                args={
-                    "H": N_HEADS,
-                    "BATCH": BATCH,
-                    "HEAD_DIM": HEAD_DIM,
-                    "mode": mode,
-                },
-            ))
-
-
-@triton.testing.perf_report(configs)
-def bench_flash_attention(BATCH, H, N_CTX, HEAD_DIM, mode, provider, device="cuda"):
-    assert mode in ["fwd", "bwd"]
-    warmup = 25
-    rep = 100
-    dtype = torch.bfloat16
-    if "triton" in provider:
-        q = torch.randn((BATCH, H, N_CTX, HEAD_DIM), dtype=dtype, device=device, requires_grad=True)
-        k = torch.randn((BATCH, H, N_CTX, HEAD_DIM), dtype=dtype, device=device, requires_grad=True)
-        v = torch.randn((BATCH, H, N_CTX, HEAD_DIM), dtype=dtype, device=device, requires_grad=True)
-        if mode == "fwd" and "fp8" in provider:
-            q = q.to(torch.float8_e5m2)
-            k = k.to(torch.float8_e5m2)
-            v = v.permute(0, 1, 3, 2).contiguous()
-            v = v.permute(0, 1, 3, 2)
-            v = v.to(torch.float8_e5m2)
-        fn = lambda: attention(q, k, v)
-        if mode == "bwd":
-            o = fn()
-            do = torch.randn_like(o)
-            fn = lambda: o.backward(do, retain_graph=True)
-        ms = triton.testing.do_bench(fn, warmup=warmup, rep=rep)
-    if provider == "flash":
-        qkv = torch.randn((BATCH, N_CTX, 3, H, HEAD_DIM), dtype=dtype, device=device, requires_grad=True)
-        fn = lambda: flash_attn_func(qkv, causal=False)
-        if mode == "bwd":
-            o = fn()
-            do = torch.randn_like(o)
-            fn = lambda: o.backward(do, retain_graph=True)
-        ms = triton.testing.do_bench(fn, warmup=warmup, rep=rep)
-    flops_per_matmul = 2.0 * BATCH * H * N_CTX * N_CTX * HEAD_DIM
-    total_flops = 2 * flops_per_matmul
-    if mode == "bwd":
-        total_flops *= 2.5  # 2.0(bwd) + 0.5(recompute)
-    return total_flops / ms * 1e-9
-
-
-if __name__ == "__main__":
-    # only works on post-Ampere GPUs right now
-    bench_flash_attention.run(save_path=".", print_data=True)

csrc/attn/vsa/vsa.py

@@ -1,47 +0,0 @@
-import torch
-try:
-    from vsa_cuda import block_sparse_fwd, block_sparse_bwd
-except ImportError:
-    block_sparse_fwd = None
-    block_sparse_bwd = None
-from .block_sparse_attn_triton import attention_sparse as block_sparse_attn_triton
-
-class BlockSparseAttentionFunction(torch.autograd.Function):
-    @staticmethod
-    def forward(ctx, q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num):
-        o, lse = block_sparse_fwd(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num)
-        ctx.save_for_backward(q, k, v, o, lse, k2q_block_sparse_index, k2q_block_sparse_num)
-        return o
-
-    @staticmethod
-    def backward(ctx, grad_output):
-        q, k, v, o, lse, k2q_block_sparse_index, k2q_block_sparse_num = ctx.saved_tensors
-        grad_q, grad_k, grad_v = block_sparse_bwd(
-            q, k, v, o, lse, grad_output, k2q_block_sparse_index, k2q_block_sparse_num
-        )
-        return grad_q, grad_k, grad_v, None, None, None, None
-
-
-@torch._dynamo.disable
-def block_sparse_attn(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num):
-    """
-    Differentiable block sparse attention function.
-    
-    Args:
-        q: Query tensor [batch_size, num_heads, seq_len_q, head_dim]
-        k: Key tensor [batch_size, num_heads, seq_len_kv, head_dim]
-        v: Value tensor [batch_size, num_heads, seq_len_kv, head_dim]
-        q2k_block_sparse_index: Indices for query-to-key sparse blocks
-        q2k_block_sparse_num: Number of sparse blocks for each query block
-        k2q_block_sparse_index: Indices for key-to-query sparse blocks (for backward pass)
-        k2q_block_sparse_num: Number of sparse blocks for each key block (for backward pass)
-    
-    Returns:
-        output: Attention output tensor [batch_size, num_heads, seq_len_q, head_dim]
-    """
-    if block_sparse_fwd is not None:
-        return BlockSparseAttentionFunction.apply(
-            q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num
-        )
-    else:
-        return block_sparse_attn_triton(q, k, v, q2k_block_sparse_index, q2k_block_sparse_num, k2q_block_sparse_index, k2q_block_sparse_num)

docker/Dockerfile.python3.10

@@ -1,7 +1,9 @@
-FROM nvidia/cuda:12.4.1-devel-ubuntu20.04
+FROM nvidia/cuda:12.8.0-cudnn-devel-ubuntu22.04
 
 ENV DEBIAN_FRONTEND=noninteractive
 
+SHELL ["/bin/bash", "-c"]
+
 WORKDIR /FastVideo
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
@@ -9,17 +11,25 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     git \
     ca-certificates \
     openssh-server \
+    zsh \
+    vim \
+    curl \
+    gcc-11 \
+    g++-11 \
+    clang-11 \
     && rm -rf /var/lib/apt/lists/*
 
-RUN wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh && \
-    bash Miniconda3-latest-Linux-x86_64.sh -b -p /opt/conda && \
-    rm Miniconda3-latest-Linux-x86_64.sh
+# Set up C++20 compilers for ThunderKittens
+RUN update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
 
-ENV PATH=/opt/conda/bin:$PATH
+# Set CUDA environment variables
+ENV CUDA_HOME=/usr/local/cuda-12.8
+ENV PATH=${CUDA_HOME}/bin:${PATH}
+ENV LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
 
-RUN conda create --name fastvideo-dev python=3.10.0 -y
-
-SHELL ["/bin/bash", "-c"]
+# Install uv and source its environment
+RUN curl -LsSf https://astral.sh/uv/install.sh | sh && \
+    echo 'source $HOME/.local/bin/env' >> /root/.bashrc
 
 # Copy just the pyproject.toml first to leverage Docker cache
 COPY pyproject.toml ./
@@ -27,22 +37,30 @@ COPY pyproject.toml ./
 # Create a dummy README to satisfy the installation
 RUN echo "# Placeholder" > README.md
 
-RUN conda run -n fastvideo-dev pip install --no-cache-dir --upgrade pip && \
-    conda run -n fastvideo-dev pip install --no-cache-dir .[dev] && \
-    conda run -n fastvideo-dev pip install --no-cache-dir flash-attn==2.7.4.post1 --no-build-isolation && \
-    conda clean -afy
+# Create and activate virtual environment with specific Python version and seed
+RUN source $HOME/.local/bin/env && \
+    uv venv --python 3.10 --seed /opt/venv && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir --upgrade pip && \
+    uv pip install --no-cache-dir .[dev] && \
+    uv pip install --no-cache-dir https://github.com/mjun0812/flash-attention-prebuild-wheels/releases/download/v0.5.4/flash_attn-2.8.3%2Bcu128torch2.9-cp310-cp310-linux_x86_64.whl
 
 COPY . .
 
-RUN conda run -n fastvideo-dev pip install --no-cache-dir -e .[dev]
+# Install dependencies using uv and set up shell configuration
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir -e .[dev] && \
+    git config --unset-all http.https://github.com/.extraheader || true && \
+    echo 'source /opt/venv/bin/activate' >> /root/.bashrc && \
+    echo 'if [ -n "$ZSH_VERSION" ] && [ -f ~/.zshrc ]; then . ~/.zshrc; elif [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
 
-# Remove authentication headers
-RUN git config --unset-all http.https://github.com/.extraheader || true
+# Install FastVideo Unified Kernel
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    cd fastvideo-kernel && \
+    git submodule update --init --recursive && \
+    ./build.sh
 
-# Set up automatic conda environment activation for all shells
-RUN echo 'source /opt/conda/etc/profile.d/conda.sh' >> /root/.bashrc && \
-    echo 'conda activate fastvideo-dev' >> /root/.bashrc && \
-    # Ensure .bashrc is sourced for SSH login shells
-    echo 'if [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
 
-EXPOSE 22
+EXPOSE 22

docker/Dockerfile.python3.11

@@ -1,7 +1,9 @@
-FROM nvidia/cuda:12.4.1-devel-ubuntu20.04
+FROM nvidia/cuda:12.8.0-cudnn-devel-ubuntu22.04
 
 ENV DEBIAN_FRONTEND=noninteractive
 
+SHELL ["/bin/bash", "-c"]
+
 WORKDIR /FastVideo
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
@@ -9,17 +11,25 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     git \
     ca-certificates \
     openssh-server \
+    zsh \
+    vim \
+    curl \
+    gcc-11 \
+    g++-11 \
+    clang-11 \
     && rm -rf /var/lib/apt/lists/*
 
-RUN wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh && \
-    bash Miniconda3-latest-Linux-x86_64.sh -b -p /opt/conda && \
-    rm Miniconda3-latest-Linux-x86_64.sh
+# Set up C++20 compilers for ThunderKittens
+RUN update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
 
-ENV PATH=/opt/conda/bin:$PATH
+# Set CUDA environment variables
+ENV CUDA_HOME=/usr/local/cuda-12.8
+ENV PATH=${CUDA_HOME}/bin:${PATH}
+ENV LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
 
-RUN conda create --name fastvideo-dev python=3.11.11 -y
-
-SHELL ["/bin/bash", "-c"]
+# Install uv and source its environment
+RUN curl -LsSf https://astral.sh/uv/install.sh | sh && \
+    echo 'source $HOME/.local/bin/env' >> /root/.bashrc
 
 # Copy just the pyproject.toml first to leverage Docker cache
 COPY pyproject.toml ./
@@ -27,22 +37,30 @@ COPY pyproject.toml ./
 # Create a dummy README to satisfy the installation
 RUN echo "# Placeholder" > README.md
 
-RUN conda run -n fastvideo-dev pip install --no-cache-dir --upgrade pip && \
-    conda run -n fastvideo-dev pip install --no-cache-dir .[dev] && \
-    conda run -n fastvideo-dev pip install --no-cache-dir flash-attn==2.7.4.post1 --no-build-isolation && \
-    conda clean -afy
+# Create and activate virtual environment with specific Python version and seed
+RUN source $HOME/.local/bin/env && \
+    uv venv --python 3.11 --seed /opt/venv && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir --upgrade pip && \
+    uv pip install --no-cache-dir .[dev] && \
+    uv pip install --no-cache-dir https://github.com/mjun0812/flash-attention-prebuild-wheels/releases/download/v0.5.4/flash_attn-2.8.3%2Bcu128torch2.9-cp311-cp311-linux_x86_64.whl
 
 COPY . .
 
-RUN conda run -n fastvideo-dev pip install --no-cache-dir -e .[dev]
+# Install dependencies using uv and set up shell configuration
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir -e .[dev] && \
+    git config --unset-all http.https://github.com/.extraheader || true && \
+    echo 'source /opt/venv/bin/activate' >> /root/.bashrc && \
+    echo 'if [ -n "$ZSH_VERSION" ] && [ -f ~/.zshrc ]; then . ~/.zshrc; elif [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
 
-# Remove authentication headers
-RUN git config --unset-all http.https://github.com/.extraheader || true
+# Install FastVideo Unified Kernel
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    cd fastvideo-kernel && \
+    git submodule update --init --recursive && \
+    ./build.sh
 
-# Set up automatic conda environment activation for all shells
-RUN echo 'source /opt/conda/etc/profile.d/conda.sh' >> /root/.bashrc && \
-    echo 'conda activate fastvideo-dev' >> /root/.bashrc && \
-    # Ensure .bashrc is sourced for SSH login shells
-    echo 'if [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
 
-EXPOSE 22
+EXPOSE 22

docker/Dockerfile.python3.12

@@ -43,7 +43,7 @@ RUN source $HOME/.local/bin/env && \
     source /opt/venv/bin/activate && \
     uv pip install --no-cache-dir --upgrade pip && \
     uv pip install --no-cache-dir .[dev] && \
-    uv pip install --no-cache-dir flash-attn==2.8.0.post2 --no-build-isolation
+    uv pip install --no-cache-dir https://github.com/mjun0812/flash-attention-prebuild-wheels/releases/download/v0.5.4/flash_attn-2.8.3%2Bcu128torch2.9-cp312-cp312-linux_x86_64.whl
 
 COPY . .
 
@@ -55,18 +55,11 @@ RUN source $HOME/.local/bin/env && \
     echo 'source /opt/venv/bin/activate' >> /root/.bashrc && \
     echo 'if [ -n "$ZSH_VERSION" ] && [ -f ~/.zshrc ]; then . ~/.zshrc; elif [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
 
-# Install STA (Sliding Tile Attention)
+# Install FastVideo Unified Kernel
 RUN source $HOME/.local/bin/env && \
     source /opt/venv/bin/activate && \
-    cd csrc/attn && \
+    cd fastvideo-kernel && \
     git submodule update --init --recursive && \
-    python setup_sta.py install
+    ./build.sh
 
-# Install VSA 
-RUN source $HOME/.local/bin/env && \
-    source /opt/venv/bin/activate && \
-    cd csrc/attn && \
-    git submodule update --init --recursive && \
-    python setup_vsa.py install
-
-EXPOSE 22
+EXPOSE 22

docker/Dockerfile.python3.12.cuda12.9.1

@@ -0,0 +1,66 @@
+FROM nvidia/cuda:12.9.1-cudnn-devel-ubuntu22.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+SHELL ["/bin/bash", "-c"]
+
+WORKDIR /FastVideo
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    wget \
+    git \
+    ca-certificates \
+    openssh-server \
+    zsh \
+    vim \
+    curl \
+    gcc-11 \
+    g++-11 \
+    clang-11 \
+    && rm -rf /var/lib/apt/lists/*
+
+# Set up C++20 compilers for ThunderKittens
+RUN update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+
+# Set CUDA environment variables
+ENV CUDA_HOME=/usr/local/cuda-12.9
+ENV PATH=${CUDA_HOME}/bin:${PATH}
+ENV LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
+
+# Install uv and source its environment
+RUN curl -LsSf https://astral.sh/uv/install.sh | sh && \
+    echo 'source $HOME/.local/bin/env' >> /root/.bashrc
+
+# Copy just the pyproject.toml first to leverage Docker cache
+COPY pyproject.toml ./
+
+# Create a dummy README to satisfy the installation
+RUN echo "# Placeholder" > README.md
+
+# Create and activate virtual environment with specific Python version and seed
+RUN source $HOME/.local/bin/env && \
+    uv venv --python 3.12 --seed /opt/venv && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir --upgrade pip && \
+    uv pip install --no-cache-dir .[dev] && \
+    uv pip install --no-cache-dir flash-attn==2.8.3 --no-build-isolation
+
+COPY . .
+
+# Install dependencies using uv and set up shell configuration
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir -e .[dev] && \
+    git config --unset-all http.https://github.com/.extraheader || true && \
+    echo 'source /opt/venv/bin/activate' >> /root/.bashrc && \
+    echo 'if [ -n "$ZSH_VERSION" ] && [ -f ~/.zshrc ]; then . ~/.zshrc; elif [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
+
+# Install FastVideo Unified Kernel
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    cd fastvideo-kernel && \
+    git submodule update --init --recursive && \
+    ./build.sh
+
+
+EXPOSE 22

docker/rocm7_1.Dockerfile

@@ -0,0 +1,58 @@
+FROM rocm/pytorch:rocm7.1_ubuntu22.04_py3.10_pytorch_release_2.9.1
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+SHELL ["/bin/bash", "-c"]
+
+WORKDIR /FastVideo
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    wget \
+    git \
+    ca-certificates \
+    openssh-server \
+    zsh \
+    vim \
+    curl \
+    gcc-11 \
+    g++-11 \
+    clang-11 \
+    && rm -rf /var/lib/apt/lists/*
+
+# Set up C++20 compilers for ThunderKittens
+RUN update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+
+# Install uv and source its environment
+RUN curl -LsSf https://astral.sh/uv/install.sh | sh && \
+    echo 'source $HOME/.local/bin/env' >> /root/.bashrc
+
+# Copy just the pyproject.toml first to leverage Docker cache
+COPY pyproject_other.toml ./pyproject.toml
+
+# Create a dummy README to satisfy the installation
+RUN echo "# Placeholder" > README.md
+
+# Create and activate virtual environment with specific Python version and seed
+RUN source $HOME/.local/bin/env && \
+    uv venv --python 3.10 --seed /opt/venv && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir --upgrade pip
+
+COPY . .
+
+# Install dependencies using uv and set up shell configuration
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    uv pip install --no-cache-dir -e .[rocm] && \
+    git config --unset-all http.https://github.com/.extraheader || true && \
+    echo 'source /opt/venv/bin/activate' >> /root/.bashrc && \
+    echo 'if [ -n "$ZSH_VERSION" ] && [ -f ~/.zshrc ]; then . ~/.zshrc; elif [ -f ~/.bashrc ]; then . ~/.bashrc; fi' > /root/.profile
+
+# Install FastVideo Unified Kernel
+RUN source $HOME/.local/bin/env && \
+    source /opt/venv/bin/activate && \
+    cd fastvideo-kernel && \
+    git submodule update --init --recursive && \
+    ./build.sh --rocm
+
+EXPOSE 22

docs/Makefile

@@ -1,26 +0,0 @@
-# Minimal makefile for Sphinx documentation
-#
-
-# You can set these variables from the command line, and also
-# from the environment for the first two.
-SPHINXOPTS    ?=
-SPHINXBUILD   ?= sphinx-build
-SOURCEDIR     = source
-BUILDDIR      = build
-
-# Put it first so that "make" without argument is like "make help".
-help:
-	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
-
-.PHONY: help Makefile
-
-# Catch-all target: route all unknown targets to Sphinx using the new
-# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
-%: Makefile
-	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
-
-clean:
-	@$(SPHINXBUILD) -M clean "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
-	rm -rf "$(SOURCEDIR)/getting_started/examples"
-	rm -rf "$(SOURCEDIR)/inference/examples"
-	rm -rf "$(SOURCEDIR)/training/examples"

docs/README.md

@@ -1,20 +1,39 @@
-# FastVideo documents
+# FastVideo Documentation
 
-## Build the docs
+This directory contains the FastVideo documentation built with MkDocs.
+
+## Build the docs locally
 
 ```bash
-# Install dependencies.
-pip install -r requirements-docs.txt
+# Install dependencies
+pip install -r requirements-mkdocs.txt
 
-# Build the docs.
-make clean
-make html
+# Serve docs with live reload (recommended for development)
+mkdocs serve
+
+# Or build static site
+mkdocs build
 ```
 
-## Open the docs with your browser
+## View the docs
+
+### Development server (with live reload)
 
 ```bash
-python -m http.server -d build/html/
+mkdocs serve
 ```
 
-Launch your browser and open localhost:8000.
+Then open your browser to: http://127.0.0.1:8000
+
+### Static build
+
+```bash
+mkdocs build
+python -m http.server -d site/
+```
+
+Then open your browser to: http://localhost:8000
+
+## Automatic Deployment
+
+Documentation is automatically built and deployed to GitHub Pages when changes are pushed to the `main` branch via the `.github/workflows/docs.yml` workflow.

docs/api/fastvideo.md

@@ -0,0 +1,248 @@
+# FastVideo API Reference
+
+This page contains the complete API reference for the FastVideo library.
+
+## fastvideo
+
+### Modules
+
+| Name | Description |
+|------|-------------|
+| [attention](#fastvideoattention) | Attention mechanisms and backends for video generation |
+| [configs](#fastvideoconfigs) | Configuration classes for pipelines, models, and sampling |
+| [distributed](#fastvideodistributed) | Distributed execution and communication utilities |
+| [entrypoints](#fastvideoentrypoints) | Main API entry points for video generation |
+| [models](#fastvideomodels) | Model implementations (transformers, VAEs, schedulers) |
+| [pipelines](#fastvideopipelines) | Core pipeline classes for video diffusion |
+| [training](#fastvideotraining) | Training utilities and helpers |
+| [workflow](#fastvideoworkflow) | Workflow management and orchestration |
+| [dataset](#fastvideodataset) | Dataset handling and preprocessing |
+| [layers](#fastvideolayers) | Custom neural network layers |
+| [platforms](#fastvideoplatforms) | Platform-specific implementations |
+| [utils](#fastvideoutils) | Utility functions and helpers |
+| [worker](#fastvideoworker) | Execution workers for video generation |
+
+## fastvideo.attention
+
+::: fastvideo.attention
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.configs
+
+::: fastvideo.configs
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+### Submodules
+
+#### fastvideo.configs.pipelines
+
+::: fastvideo.configs.pipelines
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.configs.models
+
+::: fastvideo.configs.models
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.configs.sample
+
+::: fastvideo.configs.sample
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+## fastvideo.distributed
+
+::: fastvideo.distributed
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.entrypoints
+
+::: fastvideo.entrypoints
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.models
+
+::: fastvideo.models
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+### Submodules
+
+#### fastvideo.models.registry
+
+::: fastvideo.models.registry
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.models.loader
+
+::: fastvideo.models.loader
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+## fastvideo.pipelines
+
+::: fastvideo.pipelines
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+### Submodules
+
+#### fastvideo.pipelines.composed_pipeline_base
+
+::: fastvideo.pipelines.composed_pipeline_base
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.pipelines.lora_pipeline
+
+::: fastvideo.pipelines.lora_pipeline
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.pipelines.pipeline_batch_info
+
+::: fastvideo.pipelines.pipeline_batch_info
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.pipelines.pipeline_registry
+
+::: fastvideo.pipelines.pipeline_registry
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+#### fastvideo.pipelines.stages
+
+::: fastvideo.pipelines.stages
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 4
+
+## fastvideo.training
+
+::: fastvideo.training
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.workflow
+
+::: fastvideo.workflow
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.dataset
+
+::: fastvideo.dataset
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.layers
+
+::: fastvideo.layers
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.platforms
+
+::: fastvideo.platforms
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3
+
+## fastvideo.utils
+
+::: fastvideo.utils
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      heading_level: 3
+
+## fastvideo.worker
+
+::: fastvideo.worker
+    options:
+      show_source: true
+      show_root_heading: true
+      show_root_toc_entry: true
+      show_submodules: true
+      heading_level: 3

docs/api/summary.md

@@ -0,0 +1,27 @@
+# API Summary
+
+This page provides a quick overview of the main FastVideo API components.
+
+## Video Generator
+
+::: fastvideo.VideoGenerator
+    options:
+      show_root_heading: false
+      show_source: false
+      heading_level: 3
+
+## Initialization Configuration
+
+::: fastvideo.PipelineConfig
+    options:
+      show_root_heading: false
+      show_source: false
+      heading_level: 3
+
+## Sampling Configuration
+
+::: fastvideo.SamplingParam
+    options:
+      show_root_heading: false
+      show_source: false
+      heading_level: 3

docs/assets/custom.css

@@ -0,0 +1,43 @@
+.vertical-table-header th.head:not(.stub) {
+    writing-mode: sideways-lr;
+    white-space: nowrap;
+    max-width: 0;
+}
+
+/* Keep header cell paragraph content tight (avoid CSS nesting for compatibility) */
+.vertical-table-header th.head:not(.stub) p {
+    margin: 0;
+}
+
+/* Image sizing classes */
+.image-small {
+    max-width: 200px;
+    height: auto;
+}
+
+.image-medium {
+    max-width: 400px;
+    height: auto;
+}
+
+.image-large {
+    max-width: 600px;
+    height: auto;
+}
+
+.image-full {
+    max-width: 100%;
+    height: auto;
+}
+
+/* Responsive images */
+img {
+    max-width: 100%;
+    height: auto;
+}
+
+/* Center images */
+.image-center {
+    display: block;
+    margin: 0 auto;
+}

docs/assets/logos/icon_simple.svg

@@ -0,0 +1,6 @@
+<svg width="160" height="93" viewBox="0 0 160 93" fill="none" xmlns="http://www.w3.org/2000/svg">
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docs/attention/developer/index.md

@@ -0,0 +1,186 @@
+# Adding a New Attention Backend
+
+FastVideo allows integrating new attention mechanisms easily. This guide walks you through adding a new backend (e.g., `MyNewAttn`).
+
+## 1. Implement the Backend (Python)
+
+Create a new file in `fastvideo/attention/backends/` (e.g., `mynew_attn.py`).
+
+Your implementation should inherit from `AttentionBackend` defined in `abstract.py`.
+
+```python
+# fastvideo/attention/backends/mynew_attn.py
+import torch
+from .abstract import AttentionBackend
+# Import the context manager to access metadata (optional)
+from fastvideo.forward_context import get_forward_context
+
+# Import compiled kernel if applicable (see Section 2)
+try:
+    # Import from the top-level package
+    from fastvideo_kernel import my_compiled_attn_func
+except ImportError:
+    my_compiled_attn_func = None
+
+class MyNewAttnBackend(AttentionBackend):
+    def process_inputs(self, q, k, v, **kwargs):
+        # Pre-process inputs if necessary
+        return q, k, v
+
+    def forward(self, q, k, v, **kwargs):
+        # Optional: Access extra metadata passed via ForwardContext
+        # Only needed if your backend requires global state (e.g. window_size)
+        try:
+            context = get_forward_context()
+            metadata = context.attn_metadata
+            # Example: window_size = metadata.window_size
+        except (AssertionError, AttributeError):
+            # Handle case where context is not set (e.g. standard inference)
+            pass
+
+        if my_compiled_attn_func is not None:
+            return my_compiled_attn_func(q, k, v)
+        else:
+            # Fallback implementation (e.g., Triton or pure PyTorch)
+            return self.fallback_impl(q, k, v)
+```
+
+## 2. Passing Extra Information via ForwardContext (Optional)
+
+FastVideo uses a `ForwardContext` to pass global metadata (like current timestep, batch info, or custom attention configurations) to attention backends without changing the `forward` signature of every layer. **This is optional and only required if your backend needs dynamic per-step information.**
+
+To use this:
+
+1. **Set Context**: In your pipeline or generation loop, use the `set_forward_context` context manager.
+2. **Access Context**: Inside your attention backend, use `get_forward_context()`.
+
+See [`docs/attention/sta/index.md`](../sta/index.md) (Sliding Tile Attention) for an example of how complex configuration (window sizes) is passed this way.
+
+## 3. Adding Compiled Kernels (C++/CUDA)
+
+If your backend requires custom CUDA kernels, you need to add them to the `fastvideo-kernel` package.
+
+### A. Add Source Files
+
+Place your kernel implementation files in `fastvideo-kernel/csrc/attention/`.
+
+* `mynew_attn.cu` (CUDA implementation)
+* `mynew_attn.h` (Optional headers)
+
+### B. Register in Extension
+
+Update `fastvideo-kernel/csrc/common_extension.cpp` to expose your function to Python.
+
+```cpp
+// 1. Declare external function
+#ifdef COMPILE_MYNEW_ATTN
+extern torch::Tensor mynew_attn_forward(torch::Tensor q, torch::Tensor k, torch::Tensor v);
+#endif
+
+// 2. Register in module
+PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
+    // ... other kernels ...
+
+#ifdef COMPILE_MYNEW_ATTN
+    m.def("mynew_attn_fwd", torch::wrap_pybind_function(mynew_attn_forward), "My New Attention Forward");
+#endif
+}
+```
+
+### C. Update CMakeLists.txt
+
+Update `fastvideo-kernel/CMakeLists.txt` to compile your new files.
+
+**Case 1: General CUDA Kernel (Runs on all GPUs)**
+Add your source file directly to `EXTENSION_SOURCES` and define the compilation flag.
+
+```cmake
+# Add to EXTENSION_SOURCES
+list(APPEND EXTENSION_SOURCES csrc/attention/mynew_attn.cu)
+
+# Add compilation definition for common_extension.cpp
+list(APPEND COMPILE_DEFS COMPILE_MYNEW_ATTN)
+```
+
+**Case 2: ThunderKittens Kernel (Hopper H100 Only)**
+If your kernel uses ThunderKittens (TK), it requires specific architecture flags (`sm_90a`). Add it inside the `ENABLE_TK_KERNELS` block.
+
+```cmake
+if(ENABLE_TK_KERNELS)
+    # Add source only if TK is enabled
+    list(APPEND EXTENSION_SOURCES csrc/attention/mynew_attn_tk.cu)
+    
+    # Add definition to guard registration
+    list(APPEND COMPILE_DEFS TK_COMPILE_MYNEW_ATTN)
+endif()
+```
+
+### D. Expose in Python Ops
+
+Update `fastvideo-kernel/python/fastvideo_kernel/ops.py` to make the function importable and handle fallbacks gracefully.
+
+```python
+# fastvideo-kernel/python/fastvideo_kernel/ops.py
+
+# Try to load C++ extension symbols
+try:
+    from fastvideo_kernel._C import fastvideo_kernel_ops
+    mynew_attn_fwd = getattr(fastvideo_kernel_ops, "mynew_attn_fwd", None)
+except ImportError:
+    mynew_attn_fwd = None
+
+def my_compiled_attn_func(q, k, v):
+    # Runtime check: use C++ kernel if available, else fallback
+    if mynew_attn_fwd is not None:
+        return mynew_attn_fwd(q, k, v)
+    else:
+        # Call Triton/Python fallback
+        return mynew_attn_triton(q, k, v)
+```
+
+### E. Expose in Package Init
+
+Update `fastvideo-kernel/python/fastvideo_kernel/__init__.py` to export the function.
+
+```python
+from fastvideo_kernel.ops import (
+    my_compiled_attn_func,
+    # ...
+)
+
+__all__ = [
+    "my_compiled_attn_func",
+    # ...
+]
+```
+
+## 4. Register the Backend
+
+Update `fastvideo/attention/backends/__init__.py` to export your new class.
+
+```python
+from .mynew_attn import MyNewAttnBackend
+```
+
+## 5. Platform Integration
+
+If your backend requires specific platform checks (e.g., checking for H100 support), handle that in `fastvideo/platforms/cuda.py` or within your backend's `__init__`.
+
+## 6. Add Documentation
+
+Create a new documentation page for your backend to explain its usage, installation (if custom kernels are needed), and features.
+
+1. **Create Directory**: `docs/attention/mynew_attn/`
+2. **Create Index**: `docs/attention/mynew_attn/index.md`
+3. **Update Navigation**: Add an entry to `mkdocs.yml` under the "Attention" tab.
+
+## Checklist
+
+* [ ] Created `fastvideo/attention/backends/mynew_attn.py`.
+* [ ] (Optional) Added CUDA kernels in `fastvideo-kernel/csrc/attention/`.
+* [ ] (Optional) Updated `common_extension.cpp` and `CMakeLists.txt`.
+* [ ] (Optional) Exposed kernel in `fastvideo-kernel/python/fastvideo_kernel/ops.py`.
+* [ ] (Optional) Exported kernel in `fastvideo-kernel/python/fastvideo_kernel/__init__.py`.
+* [ ] Implemented `forward` method respecting the standard signature.
+* [ ] Added unit tests in `tests/`.
+* [ ] Added documentation in `docs/attention/` and updated `mkdocs.yml`.

docs/attention/index.md

@@ -0,0 +1,53 @@
+# FastVideo Attention Kernels
+
+FastVideo provides highly optimized custom attention kernels to accelerate video generation.
+
+## Supported Kernels
+
+* **[Video Sparse Attention (VSA)](vsa/index.md)**: Sparse attention mechanism selecting top-k blocks.
+* **[Sliding Tile Attention (STA)](sta/index.md)**: Optimized attention for window-based video generation.
+
+## General Build Instructions
+
+These instructions apply to building the `fastvideo-kernel` package from source, which includes both STA and VSA kernels.
+
+### Prerequisites
+
+* **PyTorch**: 2.5.0+
+* **CUDA**: 12.4+ (12.8 recommended for best performance)
+* **C++ Compiler**: GCC 11+ (C++20 support required for ThunderKittens)
+
+Install system dependencies:
+
+```bash
+sudo apt update
+sudo apt install -y gcc-11 g++-11 clang-11 ninja-build
+
+# Set gcc-11 as default
+sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+```
+
+Set up your CUDA environment variables (adjust version as needed):
+
+```bash
+export CUDA_HOME=/usr/local/cuda-12.8
+export PATH=${CUDA_HOME}/bin:${PATH}
+export LD_LIBRARY_PATH=${CUDA_HOME}/lib64:$LD_LIBRARY_PATH
+```
+
+### Compile and Install
+
+Clone the repository and build the kernel:
+
+```bash
+# Clone recursively to get ThunderKittens submodule
+git clone https://github.com/hao-ai-lab/FastVideo.git
+cd FastVideo/fastvideo-kernel
+
+# Build and install
+./build.sh
+```
+
+The build script automatically detects your GPU architecture:
+* **H100 (sm_90a)**: Compiles optimized C++ ThunderKittens kernels.
+* **Other (A100, etc.)**: Skips C++ compilation; installs Python package with Triton kernels.

docs/attention/sta/index.md

@@ -0,0 +1,36 @@
+# Sliding Tile Attention (STA)
+
+Optimized attention for window-based video generation (e.g., HunyuanVideo).
+
+## Installation
+
+STA is included in the `fastvideo-kernel` package. See the [main Attention page](../index.md) for build instructions.
+
+## Usage
+
+```python
+from fastvideo_kernel import sliding_tile_attention
+
+# q, k, v: [batch_size, num_heads, seq_length, head_dim]
+# window_size: List of (t, h, w) tiles. Tile size is (6, 8, 8).
+# text_length: Number of text tokens (0-256)
+
+out = sliding_tile_attention(
+    q, k, v, 
+    window_size=[(3, 3, 3)],  # Example window
+    text_length=256
+)
+```
+
+## Citation
+
+If you use Sliding Tile Attention in your research, please cite:
+
+```bibtex
+@article{zhang2025fast,
+  title={Fast video generation with sliding tile attention},
+  author={Zhang, Peiyuan and Chen, Yongqi and Su, Runlong and Ding, Hangliang and Stoica, Ion and Liu, Zhengzhong and Zhang, Hao},
+  journal={arXiv preprint arXiv:2502.04507},
+  year={2025}
+}
+```

docs/attention/vsa/index.md

@@ -0,0 +1,36 @@
+# Video Sparse Attention (VSA)
+
+Sparse attention mechanism selecting top-k blocks.
+
+## Installation
+
+VSA is included in the `fastvideo-kernel` package. See the [main Attention page](../index.md) for build instructions.
+
+## Usage
+
+```python
+from fastvideo_kernel import video_sparse_attn
+
+# q, k, v: [batch_size, num_heads, seq_len, head_dim]
+# variable_block_sizes: Number of valid tokens per block
+# topk: Number of blocks to attend
+
+output = video_sparse_attn(
+    q, k, v, 
+    variable_block_sizes=block_sizes, 
+    topk=32
+)
+```
+
+## Citation
+
+If you use Video Sparse Attention in your research, please cite:
+
+```bibtex
+@article{zhang2025vsa,
+  title={Vsa: Faster video diffusion with trainable sparse attention},
+  author={Zhang, Peiyuan and Chen, Yongqi and Huang, Haofeng and Lin, Will and Liu, Zhengzhong and Stoica, Ion and Xing, Eric and Zhang, Hao},
+  journal={arXiv preprint arXiv:2505.13389},
+  year={2025}
+}
+```

docs/contributing/developer_env/docker.md

@@ -1,14 +1,14 @@
-(docker)=
+
 # 🐳 Using the FastVideo Docker Image
 
 If you prefer a containerized development environment or want to avoid managing dependencies manually, you can use our prebuilt Docker image:
 
-**Image:** [`ghcr.io/hao-ai-lab/fastvideo/fastvideo-dev:latest`](https://ghcr.io/hao-ai-lab/fastvideo/fastvideo-dev)
+**Images:** [`ghcr.io/hao-ai-lab/fastvideo/fastvideo-dev:py3.12-latest`](https://ghcr.io/hao-ai-lab/fastvideo/fastvideo-dev)
 
 ## Starting the container
 
 ```bash
-docker run --gpus all -it ghcr.io/hao-ai-lab/fastvideo/fastvideo-dev:latest
+docker run --gpus all -it ghcr.io/hao-ai-lab/fastvideo/fastvideo-dev:py3.12-latest
 ```
 
 This will:

docs/contributing/developer_env/index.md

@@ -3,11 +3,3 @@
 # 🧰 Developer Environment
 
 Accelerate your FastVideo development workflow by leveraging Docker images and cloud GPUs for efficient experimentation and reproducible environments.
-
-:::{toctree}
-:caption: Contents
-:maxdepth: 1
-
-docker
-runpod
-:::

docs/contributing/developer_env/runpod.md

@@ -1,4 +1,3 @@
-(runpod)=
 
 # 📦 Developing FastVideo on RunPod
 
@@ -6,11 +5,11 @@ You can easily use the FastVideo Docker image as a custom container on [RunPod](
 
 ## Creating a new pod
 
-Choose a GPU that supports CUDA 12.4
+Choose a GPU that supports CUDA 12.8
 
 Pick 1 or 2 L40S GPU(s)
 
-![RunPod CUDA selection](../../_static/images/runpod_cuda.png)
+![RunPod CUDA selection](../../assets/images/runpod_cuda.png)
 
 When creating your pod template, use this image:
 
@@ -24,11 +23,11 @@ Paste Container Start Command to support SSH ([RunPod Docs](https://docs.runpod.
 bash -c "apt update;DEBIAN_FRONTEND=noninteractive apt-get install openssh-server -y;mkdir -p ~/.ssh;cd $_;chmod 700 ~/.ssh;echo \"$PUBLIC_KEY\" >> authorized_keys;chmod 700 authorized_keys;service ssh start;sleep infinity"
 ```
 
-![RunPod template configuration](../../_static/images/runpod_template.png)
+![RunPod template configuration](../../assets/images/runpod_template.png)
 
 After deploying, the pod will take a few minutes to pull the image and start the SSH service.
 
-![RunPod ssh](../../_static/images/runpod_ssh.png)
+![RunPod ssh](../../assets/images/runpod_ssh.png)
 
 ## Working with the pod
 

docs/contributing/overview.md

@@ -1,4 +1,3 @@
-(developer-overview)=
 
 # 🛠️ Contributing to FastVideo
 
@@ -7,7 +6,7 @@ Thank you for your interest in contributing to FastVideo. We want to make the pr
 Our community is open to everyone and welcomes any contributions no matter how large or small.
 
 # Developer Environment:
-Do make sure you have CUDA 12.4 installed and supported. FastVideo currently only support Linux and CUDA GPUs, but we hope to support other platforms in the future.
+Do make sure you have CUDA 12.4 installed and supported. FastVideo currently only supports Linux and CUDA GPUs, but we hope to support other platforms in the future.
 
 We recommend using a fresh Python 3.10 Conda environment to develop FastVideo:
 
@@ -22,10 +21,20 @@ source ~/.bashrc
 Create and activate a Conda environment for FastVideo:
 
 ```
-conda create -n fastvideo python=3.10 -y
+conda create -n fastvideo python=3.12 -y
 conda activate fastvideo
 ```
 
+Install `uv` (optional, but recommended):
+
+From instructions on [uv](https://astral.sh/uv/):
+
+```
+curl -LsSf https://astral.sh/uv/install.sh | sh
+# or 
+wget -qO- https://astral.sh/uv/install.sh | sh
+```
+
 Clone the FastVideo repository and go to the FastVideo directory:
 
 ```
@@ -36,10 +45,10 @@ git clone https://github.com/hao-ai-lab/FastVideo.git && cd FastVideo
 Now you can install FastVideo and setup git hooks for running linting. By using `pre-commit`, the linters will run and have to pass before you'll be able to make a commit.
 
 ```bash
-pip install -e .[dev]
+uv pip install -e .[dev]
 
 # Can also install flash-attn (optional)
-pip install flash-attn==2.7.4.post1 --no-build-isolation 
+uv pip install flash-attn --no-build-isolation 
 
 # Linting, formatting and static type checking
 pre-commit install --hook-type pre-commit --hook-type commit-msg
@@ -50,3 +59,18 @@ pre-commit run --all-files
 # Unit tests
 pytest tests/
 ```
+
+If you are on a Hopper GPU, you should also install [FA3](https://github.com/Dao-AILab/flash-attention) for much better performance:
+
+```
+git clone https://github.com/Dao-AILab/flash-attention.git && cd flash-attention/hopper
+
+# make sure you have ninja installed
+uv pip install ninja
+
+python setup.py install
+```
+
+## Testing
+
+Please refer to the [Testing Guide](testing.md) for more information on how to add and run tests in FastVideo.

docs/contributing/profiling.md

@@ -0,0 +1,53 @@
+# Profiling FastVideo
+
+!!! warning
+    Profiling is only intended for FastVideo developers and maintainers to understand the proportion of time spent in different parts of the codebase. **FastVideo end-users should never turn on profiling** as it will significantly slow down inference.
+
+## Profiling with PyTorch
+
+FastVideo exposes a process-wide torch profiler that you can enable via environment variables. Set `FASTVIDEO_TORCH_PROFILER_DIR` to an absolute directory path to start collecting traces, and specify the regions you want recorded with `FASTVIDEO_TORCH_PROFILE_REGIONS`:
+
+```bash
+FASTVIDEO_TORCH_PROFILER_DIR=/mnt/traces/fastvideo \
+FASTVIDEO_TORCH_PROFILE_REGIONS="profiler_region_model_loading,profiler_region_training_step"
+```
+
+All profiled regions must be registered in `fastvideo.profiler`; the current list includes:
+
+- `profiler_region_model_loading` — pipeline/module loading
+- `profiler_region_inference_pre_denoising`
+- `profiler_region_inference_denoising`
+- `profiler_region_inference_post_denoising`
+- `profiler_region_training_checkpoint_saving`
+- `profiler_region_training_dit`
+- `profiler_region_training_validation`
+- `profiler_region_training_epoch`
+- `profiler_region_training_step`
+- `profiler_region_training_backward`
+- `profiler_region_training_optimizer`
+- `profiler_region_distillation_teacher_forward`
+- `profiler_region_distillation_student_forward`
+- `profiler_region_distillation_loss`
+- `profiler_region_distillation_update`
+
+While profiling is enabled, FastVideo records additional annotations:
+
+- `fastvideo.region::<name>` spans are emitted when entering a region.
+- `fastvideo.profiler.enable_collection` / `fastvideo.profiler.disable_collection` events mark when torch profiler collection is toggled on or off.
+
+Only one profiler instance is created per process; subsequent pipelines reuse the same controller. If you set `FASTVIDEO_TORCH_PROFILE_REGIONS` incorrectly (e.g. misspelled name), FastVideo logs a warning and ignores that entry.
+
+Additional knobs:
+
+- `FASTVIDEO_TORCH_PROFILER_RECORD_SHAPES`
+- `FASTVIDEO_TORCH_PROFILER_WITH_PROFILE_MEMORY`
+- `FASTVIDEO_TORCH_PROFILER_WITH_STACK`
+- `FASTVIDEO_TORCH_PROFILER_WITH_FLOPS`
+
+Traces can be visualized using <https://ui.perfetto.dev/>.
+
+### Best Practices
+
+- Keep the profiled step count small; traces can be large and slow down job shutdown while the profiler flushes data.
+- After profiling, clean up trace directories to avoid filling disk storage.
+- When adding new regions, register them in `fastvideo.profiler` and wrap the corresponding code block with `with self.profiler_controller.region("your_region"):` or the `@profile_region` decorator.

docs/contributing/testing.md

@@ -0,0 +1,131 @@
+# Testing in FastVideo
+
+This guide explains how to add and run tests in FastVideo. The testing suite is divided into several categories to ensure correctness across components, training workflows, and inference quality.
+
+## Test Types
+
+* **Unit Tests**: Located in `fastvideo/tests/dataset`, `fastvideo/tests/entrypoints`, and `fastvideo/tests/workflow`. These test individual functions and classes.
+* **Component Tests**: Located in `fastvideo/tests/encoders`, `fastvideo/tests/transformers`, and `fastvideo/tests/vaes`. These verify the loading and basic functionality of model components.
+* **SSIM Tests**: Located in `fastvideo/tests/ssim`. These are regression tests that compare generated videos against reference videos using the Structural Similarity Index Measure (SSIM) to detect quality degradation.
+* **Training Tests**: Located in `fastvideo/tests/training`. These validate training loops, loss calculations, and specific training techniques like LoRA, Distillation, and VSA.
+* **Inference Tests**: Located in `fastvideo/tests/inference`. These test specialized inference pipelines and optimizations (e.g., STA, V-MoBA).
+
+For now, we will focus on **SSIM Tests**.
+
+## SSIM Tests
+
+SSIM tests are located in `fastvideo/tests/ssim`. These tests generate videos using specific models and parameters, and compare them against reference videos to ensure that changes in the codebase do not degrade generation quality or alter the output unexpectedly.
+
+!!! note
+    If you are adding an SSIM test, this serves as a safeguard. Any future code changes that break or cause errors with the specific arguments and configurations you defined will trigger a failure. Therefore, it is important to include multiple settings and arguments that cover the core features of your new pipeline to ensure robust regression testing.
+
+### Directory Structure
+
+```
+fastvideo/tests/ssim/
+├── <GPU>_reference_videos/   # Reference videos organized by GPU type (e.g., L40S_reference_videos)
+│   ├── <Model_Name>/
+│   │   ├── <Backend>/        # e.g., FLASH_ATTN, TORCH_SDPA
+│   │   │   └── <Video_File>
+├── test_causal_similarity.py
+├── test_inference_similarity.py
+├── update_reference_videos.sh
+└── ...
+```
+
+### Adding a New SSIM Test
+
+To add a new SSIM test, follow these steps:
+
+1. **Create or Update a Test File**: You can add a new test function to an existing file (like `test_inference_similarity.py`) or create a new one if testing a distinct category of models.
+
+2. **Define Model Parameters**: Define the configuration for the model you want to test. This includes model path, dimensions, inference steps, and other generation parameters. **Note:** Consider using lower `num_inference_steps` or reduced resolution (e.g., 480p instead of 720p) to keep test execution time reasonable, provided it doesn't compromise the test's ability to detect regression.
+
+   ```python
+   MY_MODEL_PARAMS = {
+       "num_gpus": 1,
+       "model_path": "organization/model-name",
+       "height": 480,
+       "width": 832,
+       "num_frames": 45,
+       "num_inference_steps": 20,
+       # ... other parameters
+   }
+   ```
+
+3. **Implement the Test Function**:
+   * Use `pytest.mark.parametrize` to run the test with different prompts, backends, and models.
+   * Set the attention backend environment variable.
+   * Initialize the `VideoGenerator`.
+   * Generate the video.
+   * Compare the generated video with the reference video using `compute_video_ssim_torchvision`.
+
+   Example structure:
+
+   ```python
+   @pytest.mark.parametrize("prompt", TEST_PROMPTS)
+   @pytest.mark.parametrize("ATTENTION_BACKEND", ["FLASH_ATTN"])
+   def test_my_model_similarity(prompt, ATTENTION_BACKEND):
+       # Setup output directories
+       # ...
+
+       # Initialize Generator
+       generator = VideoGenerator.from_pretrained(...)
+       generator.generate_video(prompt, ...)
+
+       # Compare with Reference
+       ssim_values = compute_video_ssim_torchvision(
+           reference_path, generated_path, use_ms_ssim=True
+       )
+       assert ssim_values[0] >= 0.98  # Threshold
+   ```
+
+4. **Reference Videos**:
+   * When running the test for the first time (or when updating the reference), the test will fail because the reference video is missing. The generated video will be saved in `fastvideo/tests/ssim/generated_videos`.
+   * Inspect the generated video to ensure it meets quality expectations.
+   * Move the generated video to the appropriate reference folder: `fastvideo/tests/ssim/<GPU>_reference_videos/<Model>/<Backend>/`.
+   * You can use the helper script `update_reference_videos.sh` to automate copying videos from `generated_videos` to `L40S_reference_videos`. Note: Check the script to ensure paths match your environment (it defaults to `L40S_reference_videos`).
+
+### Running Tests Locally
+
+To run the SSIM tests locally:
+
+```bash
+pytest fastvideo/tests/ssim/ -vs
+```
+
+Ensure you have the necessary GPUs available as defined in your test parameters.
+
+## Modal Workflow
+
+FastVideo uses [Modal](https://modal.com/) for running tests in a CI environment. The workflow scripts are located in `fastvideo/tests/modal/`.
+
+### `pr_test.py`
+
+The main entry point for CI tests is `fastvideo/tests/modal/pr_test.py`. This script defines Modal functions that execute the pytest suites on specific hardware (e.g., L40S, H100).
+
+### Updating Modal Configuration
+
+If you add a new test that requires:
+* **Different GPU Hardware**: You may need to change the `@app.function(gpu=...)` decorator.
+* **Longer Execution Time**: Increase the `timeout` parameter.
+* **New Environment Variables/Secrets**: Add them to `secrets=[...]` or the image environment. For example, if your model is gated on Hugging Face, ensure `HF_API_KEY` is passed.
+
+For SSIM tests, the `run_ssim_tests` function in `pr_test.py` currently runs:
+
+```python
+@app.function(gpu="L40S:2", image=image, timeout=2700, secrets=[modal.Secret.from_dict({"HF_API_KEY": os.environ.get("HF_API_KEY", "")})])
+def run_ssim_tests():
+    run_test("hf auth login --token $HF_API_KEY && pytest ./fastvideo/tests/ssim -vs")
+```
+
+If your new test file is inside `fastvideo/tests/ssim`, it will automatically be picked up by this command. However, ensure that the `gpu="L40S:2"` configuration is sufficient for your model. If your model requires more GPUs (e.g., 4 or 8), you might need to create a separate Modal function or update the existing one.
+
+### Workflow Scripts
+
+The shell script that triggers these tests in the CI pipeline is located at `.buildkite/scripts/pr_test.sh`. If you add a new test category (e.g., a new folder outside of `ssim`), you will need to:
+1. Add a new function in `fastvideo/tests/modal/pr_test.py`.
+2. Add a new case in `.buildkite/scripts/pr_test.sh` to handle the new test type.
+
+!!! note
+    If you are a maintainer, you'll need to finally manually update the workflow script in Buildkite. Otherwise, a maintainer will help you update.

docs/design/overview.md

@@ -4,43 +4,45 @@ This document outlines FastVideo's architecture for developers interested in fra
 
 ## Table of Contents - Directory Structure and Files
 
-- [`fastvideo/pipelines/`](#design-pipeline-system) - Core diffusion pipeline components
-- [`fastvideo/models/`](#design-model-components) - Model implementations
-  - [`dits/`](#design-transformer-models) - Transformer-based diffusion models
-  - [`vaes/`](#design-vae-variational-auto-encoder) - Variational autoencoders
-  - [`encoders/`](#design-text-and-image-encoders) - Text and image encoders
-  - [`schedulers/`](#design-schedulers) - Diffusion schedulers
-- [`fastvideo/attention/`](#design-optimized-attention) - Optimized attention implementations
-- [`fastvideo/distributed/`](#design-distributed-processing) - Distributed computing utilities
-- [`fastvideo/layers/`](#design-tensor-parallelism) - Custom neural network layers
-- [`fastvideo/platforms/`](#design-platforms) - Hardware platform abstractions
-- [`fastvideo/worker/`](#design-executor-and-worker-abstractions) - Multi-GPU process management
-- [`fastvideo/fastvideo_args.py`](#design-fastvideo-args) - Argument handling
-- [`fastvideo/forward_context.py`](#design-forwardcontext) - Forward pass context management
+- [`fastvideo/pipelines/`](#pipeline-system) - Core diffusion pipeline components
+- [`fastvideo/models/`](#model-components) - Model implementations
+  - [`dits/`](#transformer-models) - Transformer-based diffusion models
+  - [`vaes/`](#vae-variational-auto-encoder) - Variational autoencoders
+  - [`encoders/`](#text-and-image-encoders) - Text and image encoders
+  - [`schedulers/`](#schedulers) - Diffusion schedulers
+- [`fastvideo/attention/`](#optimized-attention) - Optimized attention implementations
+- [`fastvideo/distributed/`](#distributed-processing) - Distributed computing utilities
+- [`fastvideo/layers/`](#tensor-parallelism) - Custom neural network layers
+- [`fastvideo/platforms/`](#platforms) - Hardware platform abstractions
+- [`fastvideo/worker/`](#executor-and-worker-system) - Multi-GPU process management
+- [`fastvideo/fastvideo_args.py`](#fastvideoargs) - Argument handling
+- [`fastvideo/forward_context.py`](#forward-context-management) - Forward pass context management
 - `fastvideo/utils.py` - Utility functions
-- [`fastvideo/logger.py`](#design-logger) - Logging infrastructure
+- [`fastvideo/logger.py`](#logger) - Logging infrastructure
 
 ## Core Architecture
 
 FastVideo separates model components from execution logic with these principles:
+
 - **Component Isolation**: Models (encoders, VAEs, transformers) are isolated from execution (pipelines, stages, distributed processing)
 - **Modular Design**: Components can be independently replaced
 - **Distributed Execution**: Supports various parallelism strategies (Tensor, Sequence)
 - **Custom Attention Backends**: Components can support and use different Attention implementations
 - **Pipeline Abstraction**: Consistent interface across diffusion models
 
-(design-fastvideo-args)=
 ## FastVideoArgs
 
 The `FastVideoArgs` class in `fastvideo/fastvideo_args.py` serves as the central configuration system for FastVideo. It contains all parameters needed to control model loading, inference configuration, performance optimization settings, and more.
 
 Key features include:
+
 - **Command-line Interface**: Automatic conversion between CLI arguments and dataclass fields
 - **Configuration Groups**: Organized by functional areas (model loading, video params, optimization settings)
 - **Context Management**: Global access to current settings via `get_current_fastvideo_args()`
 - **Parameter Validation**: Ensures valid combinations of settings
 
 Common configuration areas:
+
 - **Model paths and loading options**: `model_path`, `trust_remote_code`, `revision`
 - **Distributed execution settings**: `num_gpus`, `tp_size`, `sp_size`
 - **Video generation parameters**: `height`, `width`, `num_frames`, `num_inference_steps`
@@ -61,7 +63,6 @@ with set_current_fastvideo_args(fastvideo_args):
     result = generate_video()
 ```
 
-(design-pipeline-system)=
 ## Pipeline System
 
 ### `ComposedPipelineBase`
@@ -92,7 +93,9 @@ class MyCustomPipeline(ComposedPipelineBase):
 ```
 
 ### Pipeline Stages
+
 Each stage handles a specific diffusion process component:
+
 - **Input Validation**: Parameter verification
 - **Text Encoding**: CLIP, LLaMA, or T5-based encoding
 - **Image Encoding**: Image input processing
@@ -108,7 +111,8 @@ def forward(self, batch: ForwardBatch, fastvideo_args: FastVideoArgs) -> Forward
     return batch
 ```
 
-(design-forwardbatch)=
+![Pipeline execution and data flow](../assets/images/pipeline.png)
+
 ### ForwardBatch
 
 Defined in `fastvideo/pipelines/pipeline_batch_info.py`, `ForwardBatch` encapsulates the data payload passed between pipeline stages. It typically holds:
@@ -120,12 +124,10 @@ Defined in `fastvideo/pipelines/pipeline_batch_info.py`, `ForwardBatch` encapsul
 
 This structure facilitates clear state transitions between stages.
 
-(design-model-components)=
 ## Model Components
 
 The `fastvideo/models/` directory contains implementations of the core neural network models used in video diffusion:
 
-(design-transformer-models)=
 ### Transformer Models
 
 Transformer networks perform the actual denoising during diffusion:
@@ -136,6 +138,7 @@ Transformer networks perform the actual denoising during diffusion:
   - `HunyuanVideoTransformer3DModel`
 
 Features include:
+
 - Text/image conditioning
 - Standardized interface for model-specific optimizations
 
@@ -152,7 +155,6 @@ def forward(
     return noise_pred  # Predicted noise residual
 ```
 
-(design-vae-variational-auto-encoder)=
 ### VAE (Variational Auto-Encoder)
 
 VAEs handle conversion between pixel space and latent space:
@@ -165,12 +167,12 @@ VAEs handle conversion between pixel space and latent space:
 These models compress image/video data to a more efficient latent representation (typically 4x-8x smaller in each dimension).
 
 FastVideo's VAE implementations include:
+
 - Efficient video batch processing
 - Memory optimization
 - Optional tiling for large frames
 - Distributed weight support
 
-(design-text-and-image-encoders)=
 ### Text and Image Encoders
 
 Encoders process conditioning inputs into embeddings:
@@ -184,11 +186,11 @@ Encoders process conditioning inputs into embeddings:
   - `CLIPVisionModel`
 
 FastVideo implements optimizations such as:
+
 - Vocab parallelism for distributed processing
 - Caching for common prompts
 - Precision-tuned computation
 
-(design-schedulers)=
 ### Schedulers
 
 Schedulers manage the diffusion sampling process:
@@ -199,6 +201,7 @@ Schedulers manage the diffusion sampling process:
   - `FlowMatchEulerDiscreteScheduler`
 
 These components control:
+
 - Diffusion timestep sequences
 - Noise prediction to latent update conversions
 - Quality/speed trade-offs
@@ -216,13 +219,18 @@ def step(
     return prev_sample
 ```
 
-(design-optimized-attention)=
+This diagram shows how models are discovered, validated, and loaded across entrypoints, executors, pipelines, and model loaders.
+
+![Model loading flow](../assets/images/load_models.png)
+
 ## Optimized Attention
 
 The `fastvideo/attention/` directory contains optimized attention implementations crucial for efficient video diffusion:
 
 ### Attention Backends
+
 Multiple implementations with automatic selection:
+
 - **FLASH_ATTN**: Optimized for supporting hardware
 - **TORCH_SDPA**: Built-in PyTorch scaled dot-product attention
 - **SLIDING_TILE_ATTN**: For very long sequences
@@ -240,17 +248,19 @@ self.attn = LocalAttention(
 # export FASTVIDEO_ATTENTION_BACKEND=FLASH_ATTN
 ```
 
+![Attention backend selector design](../assets/images/attention_backend.png)
+
 ### Attention Patterns
+
 Supports various patterns with memory optimization techniques:
+
 - **Cross/Self/Temporal/Global-Local Attention**
 - Chunking, progressive computation, optimized masking
 
-(design-distributed-processing)=
 ## Distributed Processing
 
 The `fastvideo/distributed/` directory contains implementations for distributed model execution:
 
-(design-tensor-parallelism)=
 ### Tensor Parallelism
 
 Tensor parallelism splits model weights across devices:
@@ -299,6 +309,7 @@ self.attn = DistributedAttention(
 ```
 
 ### Communication Primitives
+
 Efficient distributed operations via AllGather, AllReduce, and synchronization mechanisms.
 
 Efficient communication primitives minimize distributed overhead:
@@ -307,7 +318,6 @@ Efficient communication primitives minimize distributed overhead:
 - **Tensor-Parallel AllReduce**: Combines partial results
 - **Distributed Synchronization**: Coordinates execution
 
-(design-forwardcontext)=
 ## Forward Context Management
 
 ### ForwardContext
@@ -318,6 +328,7 @@ Defined in `fastvideo/forward_context.py`, `ForwardContext` manages execution-sp
 - **Profiling Data**: Potential hooks for performance metrics collection
 
 This context-based approach enables:
+
 - Dynamic optimization based on execution state (e.g., attention backend selection)
 - Step-specific customizations within model components
 
@@ -330,7 +341,6 @@ with set_forward_context(current_timestep, attn_metadata, fastvideo_args):
     output = model(inputs)
 ```
 
-(design-executor-and-worker-abstractions)=
 ## Executor and Worker System
 
 The `fastvideo/worker/` directory contains the distributed execution framework:
@@ -344,12 +354,14 @@ FastVideo implements a flexible execution model for distributed processing:
 - **GPU Workers**: Handle actual model execution on individual GPUs
 
 The MultiProcExecutor implementation:
+
 1. Spawns worker processes for each GPU
 2. Establishes communication channels via pipes
 3. Coordinates distributed operations across workers
 4. Handles graceful startup and shutdown of the process group
 
 Each GPU worker:
+
 1. Initializes the distributed environment
 2. Builds the pipeline for the specified model
 3. Executes requested operations on its assigned GPU
@@ -357,7 +369,6 @@ Each GPU worker:
 
 This design allows FastVideo to efficiently utilize multiple GPUs while providing a simple, unified interface for model execution.
 
-(design-platforms)=
 ## Platforms
 
 The `fastvideo/platforms/` directory provides hardware platform abstractions that enable FastVideo to run efficiently on different hardware configurations:
@@ -365,11 +376,13 @@ The `fastvideo/platforms/` directory provides hardware platform abstractions tha
 ### Platform Abstraction
 
 FastVideo's platform abstraction layer enables:
+
 - **Hardware Detection**: Automatic detection of available hardware
 - **Backend Selection**: Appropriate selection of compute kernels
 - **Memory Management**: Efficient utilization of hardware-specific memory features
 
 The primary components include:
+
 - **Platform Interface**: Defines the common API for all platform implementations
 - **CUDA Platform**: Optimized implementation for NVIDIA GPUs
 - **Backend Enum**: Used throughout the codebase for feature selection
@@ -388,8 +401,8 @@ else:
 
 The platform system is designed to be extensible for future hardware targets.
 
-(design-logger)=
 ## Logger
+
 See [PR](https://github.com/hao-ai-lab/FastVideo/pull/356)
 
 *TODO*: (help wanted) Add an environment variable that disables process-aware logging.
@@ -404,6 +417,7 @@ If you're a new contributor, here are some common areas to explore:
 4. **Hardware support**: Extend the `platforms` module for new hardware targets
 
 When adding code, follow these practices:
+
 - Use type hints for better code readability
 - Add appropriate docstrings
 - Maintain the separation between model components and execution logic

docs/distillation/data_preprocess.md

@@ -0,0 +1,42 @@
+
+# 🧱 Data Preprocess for Distillation
+
+For distillation, we use the same data preprocessing pipeline as training. Please refer to the [Training Data Preprocess](../training/data_preprocess.md) for general preprocessing steps.
+
+## Distillation-Specific Datasets
+
+### FastVideo 480P Synthetic Wan Dataset
+
+For Wan2.1 T2V distillation, we use the **FastVideo 480P Synthetic Wan dataset** ([FastVideo/Wan-Syn_77x448x832_600k](https://huggingface.co/datasets/FastVideo/Wan-Syn_77x448x832_600k)) which contains 600k synthetic latents.
+
+```bash
+# Download the preprocessed dataset
+python scripts/huggingface/download_hf.py \
+    --repo_id "FastVideo/Wan-Syn_77x448x832_600k" \
+    --local_dir "FastVideo/Wan-Syn_77x448x832_600k" \
+    --repo_type "dataset"
+```
+
+### Crush Smol Dataset
+
+For Wan2.2 TI2V distillation, we use the crush_smol dataset which includes both raw videos and preprocessed latents.
+
+```bash
+# Download dataset
+python scripts/huggingface/download_hf.py \
+    --repo_id=FastVideo/mini_i2v_dataset \
+    --local_dir=data/mini_i2v_dataset \
+    --repo_type=dataset
+```
+
+## Preprocessing for Distillation
+
+The preprocessing steps are identical to training. Run the appropriate preprocessing script based on your model:
+
+```bash
+# For Wan2.1 T2V
+bash scripts/preprocess/v1_preprocess_wan_data_t2v
+
+# For Wan2.2 TI2V  
+bash examples/distill/Wan2.2-TI2V-5B-Diffusers/crush_smol/preprocess_wan_data_ti2v_5b.sh
+```

docs/distillation/dmd.md

@@ -0,0 +1,87 @@
+# 🎯 Distillation
+
+We introduce a new finetuning strategy - **Sparse-distill**, which jointly integrates **[DMD](https://arxiv.org/abs/2405.14867)** and **[VSA](https://arxiv.org/abs/2505.13389)** in a single training process. This approach combines the benefits of both distillation to shorten diffusion steps and sparse attention to reduce attention computation, enabling much faster video generation.
+
+## 📊 Model Overview
+
+We provide two distilled models:
+
+- **[FastWan2.1-T2V-1.3B-Diffusers](https://huggingface.co/FastVideo/FastWan2.1-T2V-1.3B-Diffusers)**: 3-step inference, up to **16 FPS** on H100 GPU
+- **[FastWan2.1-T2V-14B-480P-Diffusers](https://huggingface.co/FastVideo/FastWan2.1-T2V-14B-480P-Diffusers)**: 3-step inference, up to **60x speed up** at 480P, **90x speed up** at 720P for denoising loop
+- **[FastWan2.2-TI2V-5B-FullAttn-Diffusers](https://huggingface.co/FastVideo/FastWan2.2-TI2V-5B-FullAttn-Diffusers)**: 3-step inference, up to **50x speed up** at 720P for denoising loop
+
+Both models are trained on **61×448×832** resolution but support generating videos with **any resolution** (1.3B  model mainly support 480P, 14B model support 480P and 720P, quality may degrade for different resolutions).
+
+## ⚙️ Inference
+First install [VSA](../attention/vsa/index.md). Set `MODEL_BASE` to your own model path and run:
+
+```bash
+bash scripts/inference/v1_inference_wan_dmd.sh
+```
+
+## 🗂️ Dataset
+
+We use the **FastVideo 480P Synthetic Wan dataset** ([FastVideo/Wan-Syn_77x448x832_600k](https://huggingface.co/datasets/FastVideo/Wan-Syn_77x448x832_600k)) for distillation, which contains 600k synthetic latents.
+
+### Download Dataset
+
+```bash
+# Download the preprocessed dataset
+python scripts/huggingface/download_hf.py \
+    --repo_id "FastVideo/Wan-Syn_77x448x832_600k" \
+    --local_dir "FastVideo/Wan-Syn_77x448x832_600k" \
+    --repo_type "dataset"
+```
+
+## 🚀 Training Scripts
+
+### Wan2.1 1.3B Model Sparse-Distill
+
+For the 1.3B model, we use **4 nodes with 32 H200 GPUs** (8 GPUs per node):
+
+```bash
+# Multi-node training (8 nodes, 64 GPUs total)
+sbatch examples/distill/Wan2.1-T2V/Wan-Syn-Data-480P/distill_dmd_VSA_t2v_1.3B.slurm
+```
+
+**Key Configuration:**
+- Global batch size: 64
+- Gradient accumulation steps: 2
+- Learning rate: 1e-5
+- VSA attention sparsity: 0.8
+- Training steps: 4000 (~12 hours)
+
+### Wan2.1 14B Model Sparse-Distill
+
+For the 14B model, we use **8 nodes with 64 H200 GPUs** (8 GPUs per node):
+
+```bash
+# Multi-node training (8 nodes, 64 GPUs total)
+sbatch examples/distill/Wan2.1-T2V/Wan-Syn-Data-480P/distill_dmd_VSA_t2v_14B.slurm
+```
+
+**Key Configuration:**
+- Global batch size: 64
+- Sequence parallel size: 4
+- Gradient accumulation steps: 4
+- Learning rate: 1e-5
+- VSA attention sparsity: 0.9
+- Training steps: 3000 (~52 hours)
+- HSDP shard dim: 8
+
+### Wan2.2 5B Model Sparse-Distill
+
+For the 5B model, we use **8 nodes with 64 H200 GPUs** (8 GPUs per node):
+
+```bash
+# Multi-node training (8 nodes, 64 GPUs total)
+sbatch examples/distill/Wan2.2-TI2V-5B-Diffusers/Data-free/distill_dmd_t2v_5B.sh 
+```
+
+**Key Configuration:**
+- Global batch size: 64
+- Sequence parallel size: 1
+- Gradient accumulation steps: 1
+- Learning rate: 2e-5
+- Training steps: 3000 (~12 hours)
+- HSDP shard dim: 1

docs/examples/examples_index.md

@@ -0,0 +1,12 @@
+# 💡 Examples
+
+A collection of examples demonstrating usage of FastVideo.
+
+All documented examples are autogenerated using [generate_examples.py](https://github.com/hao-ai-lab/FastVideo/blob/main/docs/generate_examples.py) from examples found in the [examples](https://github.com/hao-ai-lab/FastVideo/tree/main/examples) directory.
+
+## Examples
+
+- [Examples Distillation Index](distillation/examples/examples_distillation_index.md)
+- [Examples Training Index](training/examples/examples_training_index.md)
+- [Examples Inference Index](inference/examples/examples_inference_index.md)
+

docs/generate_examples.py

@@ -6,10 +6,11 @@ import re
 from dataclasses import dataclass, field
 from pathlib import Path
 
-ROOT_DIR = Path(__file__).parent.parent.parent.resolve()
-ROOT_DIR_RELATIVE = '../../../..'
+ROOT_DIR = Path(__file__).parent.parent.resolve()
+ROOT_DIR_RELATIVE = '../..'
 EXAMPLE_DIR = ROOT_DIR / "examples"
-EXAMPLE_DOC_DIR = ROOT_DIR / "docs/source/getting_started/examples"
+EXAMPLE_DOC_DIR = ROOT_DIR / "docs/getting_started/examples"
+GITHUB_REPO = "hao-ai-lab/FastVideo"  # Update this to your repo
 
 
 def fix_case(text: str) -> str:
@@ -71,9 +72,16 @@ class Index:
 
     def generate(self) -> str:
         content = f"# {self.title}\n\n{self.description}\n\n"
-        content += ":::{toctree}\n"
-        content += f":caption: {self.caption}\n:maxdepth: {self.maxdepth}\n"
-        content += "\n".join(self.documents) + "\n:::\n"
+        if self.caption:
+            content += f"## {self.caption}\n\n"
+        # Generate a simple list of links for MkDocs
+        for doc in self.documents:
+            # Convert document path to proper link
+            doc_link = doc.replace("\\", "/")
+            # Get just the filename for the link text
+            doc_title = fix_case(Path(doc).stem.replace("_", " ").title())
+            content += f"- [{doc_title}]({doc_link}.md)\n"
+        content += "\n"
         return content
 
 
@@ -142,30 +150,66 @@ class Example:
         return fix_case(self.path.stem.replace("_", " ").title())
 
     def generate(self) -> str:
-        # Convert the path to a relative path from __file__
-        make_relative = lambda path: ROOT_DIR_RELATIVE / path.relative_to(
-            ROOT_DIR)
+        # Create GitHub link to source
+        github_path = str(self.path.relative_to(ROOT_DIR)).replace("\\", "/")
+        github_url = f"https://github.com/{GITHUB_REPO}/blob/main/{github_path}"
+        content = f"**Source:** [{github_path}]({github_url})\n\n"
 
-        content = f"Source <gh-file:{self.path.relative_to(ROOT_DIR)}>.\n\n"
-        include = "include" if self.main_file.suffix == ".md" else \
-            "literalinclude"
-        if include == "literalinclude":
+        # Add title for code files
+        if self.main_file.suffix != ".md":
             content += f"# {self.title}\n\n"
-        content += f":::{{{include}}} {make_relative(self.main_file)}\n"  # type: ignore[no-untyped-call]
-        if include == "literalinclude":
-            content += f":language: {self.main_file.suffix[1:]}\n"
-        content += ":::\n\n"
+
+        # Include main file content
+        if self.main_file.suffix == ".md":
+            # For markdown files, include the content directly
+            with open(self.main_file, encoding='utf-8') as f:
+                content += f.read() + "\n\n"
+        else:
+            # For code files, use code blocks
+            language = self.main_file.suffix[1:] if self.main_file.suffix else ""
+            with open(self.main_file, encoding='utf-8') as f:
+                file_content = f.read()
+            content += f"```{language}\n{file_content}\n```\n\n"
 
         if not self.other_files:
             return content
 
-        content += "## Example materials\n\n"
+        content += "## Additional Files\n\n"
+        # Define binary/non-text file extensions to skip
+        binary_extensions = {
+            '.mp4', '.avi', '.mov', '.mkv', '.gif', '.jpg', '.jpeg', '.png',
+            '.webp', '.bmp', '.pdf', '.zip', '.tar', '.gz', '.mp3', '.wav'
+        }
+
         for file in sorted(self.other_files):
-            include = "include" if file.suffix == ".md" else "literalinclude"
-            content += f":::{{admonition}} {file.relative_to(self.path)}\n"
-            content += ":class: dropdown\n\n"
-            content += f":::{{{include}}} {make_relative(file)}\n:::\n"  # type: ignore[no-untyped-call]
-            content += ":::\n\n"
+            # Skip binary files
+            if file.suffix.lower() in binary_extensions:
+                continue
+
+            file_rel_path = file.relative_to(self.path)
+            # Use collapsible admonition syntax for MkDocs
+            content += f"??? note \"{file_rel_path}\"\n\n"
+
+            try:
+                if file.suffix == ".md":
+                    # Include markdown content with indentation
+                    with open(file, encoding='utf-8') as f:
+                        for line in f:
+                            content += f"    {line}"
+                else:
+                    # Include code with proper formatting
+                    language = file.suffix[1:] if file.suffix else ""
+                    with open(file, encoding='utf-8') as f:
+                        file_content = f.read()
+                    # Indent the code block for the admonition
+                    content += f"    ```{language}\n"
+                    for line in file_content.split('\n'):
+                        content += f"    {line}\n"
+                    content += "    ```\n"
+                content += "\n"
+            except UnicodeDecodeError:
+                # Skip files that can't be decoded as UTF-8
+                continue
 
         return content
 
@@ -195,7 +239,7 @@ class NestedStructure:
 
 def create_category_indices() -> dict[str, Index]:
     """Create category indices with their respective configurations."""
-    main_index_dir = ROOT_DIR / "docs/source/examples"
+    main_index_dir = ROOT_DIR / "docs/examples"
     if not main_index_dir.exists():
         main_index_dir.mkdir(parents=True)
 
@@ -203,17 +247,16 @@ def create_category_indices() -> dict[str, Index]:
         "inference":
         Index(
             path=ROOT_DIR /
-            "docs/source/inference/examples/examples_inference_index.md",
+            "docs/inference/examples/examples_inference_index.md",
             title="🚀 Examples",
             description=
-            "Inference examples demonstrate how to use FastVideo inference. We recommend starting with <project:basic.md>.",
+            "Inference examples demonstrate how to use FastVideo inference. We recommend starting with [basic.md](basic.md).",
             caption="Examples",
             maxdepth=1,
         ),
         "training":
         Index(
-            path=ROOT_DIR /
-            "docs/source/training/examples/examples_training_index.md",
+            path=ROOT_DIR / "docs/training/examples/examples_training_index.md",
             title="🚀 Examples",
             description=
             "Training examples demonstrate how to use FastVideo training.",
@@ -223,7 +266,7 @@ def create_category_indices() -> dict[str, Index]:
         "distillation":
         Index(
             path=ROOT_DIR /
-            "docs/source/distillation/examples/examples_distillation_index.md",
+            "docs/distillation/examples/examples_distillation_index.md",
             title="🚀 Examples",
             description=
             "Distillation examples demonstrate how to use FastVideo distillation.",
@@ -246,9 +289,21 @@ def find_examples(category_indices: dict[str, Index],
     examples = []
     glob_patterns = ["*.py", "*.md", "*.sh"]
 
+    # Map category names to actual directory names
+    category_dir_mapping = {
+        "distillation": "distill",  # examples/distill/ -> distillation category
+    }
+
     # Find categorised examples
     for category in category_indices:
-        category_dir = EXAMPLE_DIR / category
+        # Use mapped directory name if available, otherwise use category name
+        dir_name = category_dir_mapping.get(category, category)
+        category_dir = EXAMPLE_DIR / dir_name
+
+        # Skip if directory doesn't exist
+        if not category_dir.exists():
+            continue
+
         globs = [category_dir.glob(pattern) for pattern in glob_patterns]
         for path in itertools.chain(*globs):
             examples.append(Example(path, category))
@@ -279,19 +334,50 @@ def create_nested_structures(
                                                 dict[str,
                                                      NestedStructure]]]] = {}
 
+    # Map category names to actual directory names
+    category_dir_mapping = {
+        "distillation": "distill",
+    }
+
     for example in examples:
         if example.category not in ["training", "distillation"]:
             continue
 
-        category_dir = EXAMPLE_DIR / example.category
+        # Use mapped directory name if available
+        dir_name = category_dir_mapping.get(example.category, example.category)
+        category_dir = EXAMPLE_DIR / dir_name
         relative_path = example.path.relative_to(category_dir)
         path_parts = relative_path.parts
 
-        # For nested examples like finetune/wan_i2v_14b_480p/crush_smol
-        if len(path_parts) >= 3:
-            method = path_parts[0]  # e.g., "finetune"
-            model = path_parts[1]  # e.g., "wan_i2v_14b_480p"
-            dataset = path_parts[2]  # e.g., "crush_smol"
+        if example.category == "training":
+            # For training examples like finetune/wan_i2v_14b_480p/crush_smol
+            if len(path_parts) >= 3:
+                method = path_parts[0]  # e.g., "finetune"
+                model = path_parts[1]  # e.g., "wan_i2v_14b_480p"
+                dataset = path_parts[2]  # e.g., "crush_smol"
+
+                # Initialize nested structure
+                if example.category not in nested_structures:
+                    nested_structures[example.category] = {}
+                if method not in nested_structures[example.category]:
+                    nested_structures[example.category][method] = {}
+                if model not in nested_structures[example.category][method]:
+                    nested_structures[example.category][method][model] = {}
+
+                # Store the nested structure
+                nested_structures[
+                    example.category][method][model][dataset] = NestedStructure(
+                        category=example.category,
+                        method=method,
+                        model=model,
+                        dataset=dataset,
+                        example=example)
+
+        elif example.category == "distillation" and len(path_parts) >= 2:
+            # For distillation examples like Wan2.1-T2V/Wan-Syn-Data-480P
+            model = path_parts[0]  # e.g., "Wan2.1-T2V"
+            dataset = path_parts[1]  # e.g., "Wan-Syn-Data-480P"
+            method = "DMD"  # Default method for distillation
 
             # Initialize nested structure
             if example.category not in nested_structures:
@@ -391,7 +477,7 @@ def generate_nested_examples(nested_structures: dict[str, dict[str, dict[
             category_index.documents.append(method)
 
 
-def generate_examples(generate_main_index=False):
+def generate_examples(generate_main_index: bool = False) -> None:
     """
     Generate example documentation.
     
@@ -405,12 +491,14 @@ def generate_examples(generate_main_index=False):
     # Create the main examples index only if requested
     examples_index = None
     if generate_main_index:
-        main_index_dir = ROOT_DIR / "docs/source/examples"
+        main_index_dir = ROOT_DIR / "docs/examples"
         examples_index = Index(
             path=main_index_dir / "examples_index.md",
             title="💡 Examples",
             description=
-            "A collection of examples demonstrating usage of FastVideo.\nAll documented examples are autogenerated using <gh-file:docs/source/generate_examples.py> from examples found in <gh-file:examples>.",
+            "A collection of examples demonstrating usage of FastVideo.\n\n"
+            f"All documented examples are autogenerated using [generate_examples.py](https://github.com/{GITHUB_REPO}/blob/main/docs/generate_examples.py) "
+            f"from examples found in the [examples](https://github.com/{GITHUB_REPO}/tree/main/examples) directory.",
             caption="Examples",
             maxdepth=2)
 
@@ -447,3 +535,19 @@ def generate_examples(generate_main_index=False):
     if generate_main_index and examples_index:
         with open(examples_index.path, "w+") as f:
             f.write(examples_index.generate())
+
+
+def on_pre_build_hook(config, **kwargs):
+    """
+    MkDocs hook to generate examples before building the documentation.
+    This function is called automatically by the mkdocs-simple-hooks plugin.
+    """
+    print("Generating example documentation...")
+    generate_examples(generate_main_index=True)
+    print("Example documentation generated successfully!")
+
+
+if __name__ == "__main__":
+    print("Generating example documentation...")
+    generate_examples(generate_main_index=True)
+    print("Example documentation generated successfully!")

docs/getting_started/installation.md

@@ -0,0 +1,45 @@
+
+# 🔧 Installation
+
+FastVideo supports the following hardware platforms:
+
+- [NVIDIA CUDA](installation/gpu.md)
+- [Apple silicon](installation/mps.md)
+
+## Quick Installation
+
+### Using pip
+
+```bash
+# Create and activate a new conda environment
+conda create -n fastvideo python=3.12
+conda activate fastvideo
+
+pip install fastvideo
+```
+
+### From source
+
+```bash
+git clone https://github.com/hao-ai-lab/FastVideo.git
+cd FastVideo
+pip install -e .
+```
+
+Also optionally install flash-attn:
+
+```bash
+pip install flash-attn --no-build-isolation
+```
+
+## Hardware Requirements
+
+- **NVIDIA GPUs**: CUDA 11.8+ with compute capability 7.0+
+- **Apple Silicon**: macOS 12.0+ with M1/M2/M3 chips
+- **CPU**: x86_64 architecture (for CPU-only inference)
+
+## Next Steps
+
+- [Quick Start Guide](quick_start.md) - Get started with your first video generation
+- [Configuration](../inference/configuration.md) - Learn about configuration options
+- [Examples](../inference/examples/examples_inference_index.md) - Explore example scripts and notebooks

docs/getting_started/installation/gpu.md

@@ -6,7 +6,7 @@ Instructions to install FastVideo for NVIDIA CUDA GPUs.
 
 - **OS: Linux or Windows WSL**
 - **Python: 3.10-3.12**
-- **CUDA 12.4**
+- **CUDA 12.8**
 - **At least 1 NVIDIA GPU**
 
 ## Set up using Python
@@ -30,16 +30,8 @@ conda create -n fastvideo python=3.12 -y
 conda activate fastvideo
 ```
 
-:::{note}
-[PyTorch has deprecated the conda release channel](https://github.com/pytorch/pytorch/issues/138506). If you use `conda`, please only use it to create Python environment rather than installing packages.
-:::
-
 #### uv
 
-:::{tip}
-We highly recommend using `uv` to install FastVideo. In our experience, `uv` speeds up installation by at least 3x.
-:::
-
 Or you can create a new Python environment using [uv](https://docs.astral.sh/uv/), a very fast Python environment manager. Please follow the [documentation](https://docs.astral.sh/uv/#getting-started) to install `uv`. After installing `uv`, you can create a new Python environment using the following command:
 
 ```console
@@ -60,7 +52,7 @@ uv pip install fastvideo
 Also optionally install flash-attn:
 
 ```bash
-pip install flash-attn==2.7.4.post1 --no-build-isolation
+pip install flash-attn --no-build-isolation
 ```
 
 ### Installation from Source
@@ -87,22 +79,22 @@ uv pip install -e .
 #### Flash Attention
 
 ```bash
-pip install flash-attn==2.7.4.post1 --no-build-isolation
+pip install flash-attn --no-build-isolation
 ```
 
 ## Set up using Docker
 We also have prebuilt docker images with FastVideo dependencies pre-installed:
-[Docker Images](#docker)
+[Docker Images](../../contributing/developer_env/docker.md)
 
 ## Development Environment Setup
 
 If you're planning to contribute to FastVideo please see the following page:
-[Contributor Guide](#developer-overview)
+[Contributor Guide](../../contributing/overview.md)
 
 ## Hardware Requirements
 
 ### For Basic Inference
-- NVIDIA GPU with CUDA 12.4 support
+- NVIDIA GPU with CUDA 12.8 support
 
 ### For Lora Finetuning
 - 40GB GPU memory each for 2 GPUs with lora

docs/getting_started/installation/mps.md

@@ -31,16 +31,8 @@ conda create -n fastvideo python=3.12.4 -y
 conda activate fastvideo
 ```
 
-:::{note}
-[PyTorch has deprecated the conda release channel](https://github.com/pytorch/pytorch/issues/138506). If you use `conda`, please only use it to create Python environment rather than installing packages.
-:::
-
 #### uv
 
-:::{tip}
-We highly recommend using `uv` to install FastVideo. In our experience, `uv` speeds up installation by at least 3x.
-:::
-
 Or you can create a new Python environment using [uv](https://docs.astral.sh/uv/), a very fast Python environment manager. Please follow the [documentation](https://docs.astral.sh/uv/#getting-started) to install `uv`. After installing `uv`, you can create a new Python environment using the following command:
 
 ```console
@@ -86,7 +78,7 @@ uv pip install -e .
 ## Development Environment Setup
 
 If you're planning to contribute to FastVideo please see the following page:
-[Contributor Guide](#developer-overview)
+[Contributor Guide](../../contributing/overview.md)
 
 ## Hardware Requirements
 

docs/getting_started/quick_start.md

@@ -0,0 +1,83 @@
+# 🚀 Quick Start
+
+Get up and running with FastVideo in minutes!
+
+## Installation
+
+First, install FastVideo:
+
+```bash
+# Create and activate a new conda environment
+conda create -n fastvideo python=3.12
+conda activate fastvideo
+
+# Install FastVideo
+pip install fastvideo
+```
+
+Also optionally install flash-attn:
+
+```bash
+pip install flash-attn --no-build-isolation
+```
+
+## Basic Usage
+
+### Text-to-Video Generation
+
+```python
+from fastvideo import VideoGenerator
+
+def main():
+    # Create a video generator with a pre-trained model
+    generator = VideoGenerator.from_pretrained(
+        "Wan-AI/Wan2.1-T2V-1.3B-Diffusers",
+        num_gpus=1,  # Adjust based on your hardware
+    )
+
+    # Define a prompt for your video
+    prompt = "A curious raccoon peers through a vibrant field of yellow sunflowers, its eyes wide with interest."
+
+    # Generate the video
+    video = generator.generate_video(
+        prompt,
+        return_frames=True,  # Also return frames from this call (defaults to False)
+        output_path="my_videos/",  # Controls where videos are saved
+        save_video=True
+    )
+
+if __name__ == '__main__':
+    main()
+```
+
+### Image-to-Video Generation
+
+```python
+from fastvideo import VideoGenerator, SamplingParam
+
+def main():
+    # Create the generator
+    model_name = "Wan-AI/Wan2.1-I2V-14B-480P-Diffusers"
+    generator = VideoGenerator.from_pretrained(model_name, num_gpus=1)
+
+    # Set up parameters with an initial image
+    sampling_param = SamplingParam.from_pretrained(model_name)
+    sampling_param.image_path = "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/astronaut.jpg"
+    sampling_param.num_frames = 107
+
+    # Generate video based on the image
+    prompt = "A photograph coming to life with gentle movement"
+    generator.generate_video(prompt, sampling_param=sampling_param,
+                             output_path="my_videos/",
+                             save_video=True)
+
+if __name__ == '__main__':
+    main()
+```
+
+## Next Steps
+
+- [Installation Guide](installation.md) - Detailed installation instructions
+- [Configuration](../inference/configuration.md) - Learn about configuration options
+- [Examples](../inference/examples/) - Explore more examples
+- [Optimizations](../inference/optimizations.md) - Performance optimization tips

docs/getting_started/v1_api.md

@@ -0,0 +1,42 @@
+# V1 API
+
+FastVideo's V1 API provides a streamlined interface for video generation tasks with powerful customization options. This page documents the primary components of the API.
+
+## Video Generator
+
+This class will be the primary Python API for generating videos and images.
+
+::: fastvideo.entrypoints.video_generator.VideoGenerator
+    options:
+      show_root_heading: true
+      show_source: false
+      members:
+        - from_pretrained
+      heading_level: 3
+
+`VideoGenerator.from_pretrained()` should be the primary way of creating a new video generator.
+
+## Configuring FastVideo
+
+The following two classes `PipelineConfig` and `SamplingParam` are used to configure initialization and sampling parameters, respectively.
+
+### PipelineConfig
+
+::: fastvideo.configs.pipelines.base.PipelineConfig
+    options:
+      show_root_heading: true
+      show_source: false
+      members:
+        - from_pretrained
+        - dump_to_json
+      heading_level: 4
+
+### SamplingParam
+
+::: fastvideo.configs.sample.base.SamplingParam
+    options:
+      show_root_heading: true
+      show_source: false
+      members:
+        - from_pretrained
+      heading_level: 4

docs/index.md

@@ -0,0 +1,52 @@
+# Welcome to FastVideo
+
+<div style="text-align: center;">
+  <img src="assets/logos/logo.svg" alt="FastVideo" style="width: 60%;" />
+</div>
+
+<div style="text-align: center;">
+<strong>FastVideo is a unified inference and post-training framework for accelerated video generation.</strong>
+</div>
+
+<div style="text-align: center;">
+<script async defer src="https://buttons.github.io/buttons.js"></script>
+<a class="github-button" href="https://github.com/hao-ai-lab/FastVideo/" data-show-count="true" data-size="large" aria-label="Star">Star</a>
+<a class="github-button" href="https://github.com/hao-ai-lab/FastVideo/subscription" data-icon="octicon-eye" data-size="large" aria-label="Watch">Watch</a>
+<a class="github-button" href="https://github.com/hao-ai-lab/FastVideo/fork" data-icon="octicon-repo-forked" data-size="large" aria-label="Fork">Fork</a>
+</div>
+
+FastVideo is an inference and post-training framework for diffusion models. It features an end-to-end unified pipeline for accelerating diffusion models, starting from data preprocessing to model training, finetuning, distillation, and inference. FastVideo is designed to be modular and extensible, allowing users to easily add new optimizations and techniques. Whether it is training-free optimizations or post-training optimizations, FastVideo has you covered.
+
+<div style="text-align: center;">
+  <img src="assets/images/fastwan.png" style="width: 100%;"/>
+</div>
+
+## Key Features
+
+FastVideo has the following features:
+
+- State-of-the-art performance optimizations for inference
+  - [Sliding Tile Attention](https://arxiv.org/pdf/2502.04507)
+  - [TeaCache](https://arxiv.org/pdf/2411.19108)
+  - [Sage Attention](https://arxiv.org/abs/2410.02367)
+- E2E post-training support
+  - Data preprocessing pipeline for video data
+  - [Sparse distillation](https://hao-ai-lab.github.io/blogs/fastvideo_post_training/) for Wan2.1 and Wan2.2 using [Video Sparse Attention](https://arxiv.org/pdf/2505.13389) and [Distribution Matching Distillation](https://tianweiy.github.io/dmd2/)
+  - Support full finetuning and LoRA finetuning for state-of-the-art open video DiTs.
+  - Scalable training with FSDP2, sequence parallelism, and selective activation checkpointing, with near linear scaling to 64 GPUs.
+
+## Documentation
+
+Welcome to FastVideo! This documentation will help you get started with our unified inference and post-training framework for accelerated video generation.
+
+Use the navigation menu on the left to explore different sections:
+
+- **Getting Started**: Installation and quick start guides
+- **Inference**: Learn how to use FastVideo for video generation
+- **Training**: Data preprocessing and fine-tuning workflows
+- **Distillation**: Post-training optimization techniques
+- **Sliding Tile Attention**: Advanced attention mechanisms
+- **Video Sparse Attention**: Efficient attention for video models
+- **Design**: Framework architecture and design principles
+- **Developer Guide**: Contributing and development setup
+- **API Reference**: Complete API documentation

docs/inference/add_pipeline.md

@@ -1,4 +1,3 @@
-(add-pipeline)=
 
 # 🏗️ Adding a New Pipeline
 
@@ -46,6 +45,7 @@ FastVideo uses the Hugging Face Diffusers format for model organization:
 ### Implementing Modules
 
 Place new modules in the appropriate directories:
+
 - Encoders: `fastvideo/models/encoders/`
 - VAEs: `fastvideo/models/vaes/`
 - Transformer models: `fastvideo/models/dits/`
@@ -54,12 +54,15 @@ Place new modules in the appropriate directories:
 ### Adapting Model Layers
 
 #### Layer Replacements
+
 Replace standard PyTorch layers with FastVideo optimized versions:
+
 - nn.LayerNorm → fastvideo.layers.layernorm.RMSNorm
 - Embedding layers → fastvideo.layers.vocab_parallel_embedding modules
 - Activation functions → versions from fastvideo.layers.activation
 
 #### Distributed Linear Layers
+
 Use appropriate parallel layers for distribution:
 
 ```python
@@ -92,6 +95,7 @@ self.out_proj = RowParallelLinear(
 ```
 
 ### Attention Layers
+
 Replace standard attention with FastVideo's optimized attention:
 
 ```python
@@ -305,6 +309,7 @@ EntryClass = [MyCustomPipeline, MyOtherPipeline]
 ```
 
 The registry will automatically:
+
 1. Scan all packages under `fastvideo/pipelines/`
 2. Look for `EntryClass` variables
 3. Register pipelines using their class names as identifiers

docs/inference/cli.md

@@ -1,7 +1,7 @@
 # FastVideo CLI Inference
 
 The FastVideo CLI provides a quick way to access the FastVideo inference pipeline for video generation. For more advanced usage,
-see the Python interface [here](https://hao-ai-lab.github.io/FastVideo/inference/examples/basic.html).
+see the Python interface [here](examples/basic.md).
 
 ## Basic Usage