Files
hao-ai-lab-FastVideo/v2/tests/test_adaptive_compute.py
T
SolitaryThinker 9489c6c1dd [feat] Five more stress tests: LTX-2 A/V, weight-sync, served reward, cache-dit, nested workflows
The remaining design_v3 probes (all except 8b speculative decoding). All fit with no new runtime
primitive (148 tests pass).

#6 LTX-2 joint audio+video (§9.11) — LTX-2 declared an audio_vae required_for t2vs but never used
   it; now a single 2-stage denoise carries a synchronized audio latent (conditioned on video),
   applies per-modality CFG (guidance_per_modality), and decodes via video VAE + audio VAE → video +
   audio. Gated on requesting audio, so the T2V path is byte-identical (existing tests untouched).
   ToyAudioVAE; build_ltx2_av_program. 5 tests.

#4 Live weight-sync under in-flight serving (§9.14) — WeightSyncController makes the freeze → drain →
   transfer → bump version + invalidate → resume lifecycle explicit. Tests: a mid-flight swap corrupts
   (the hazard); draining first leaves the in-flight request bit-identical to baseline while a
   post-sync request reflects new weights; transformer-only sync, so the frozen text-encoder cache
   survives. The RL flywheel's hardest correctness. 3 tests.

#5 Reward-model-as-a-served-card (§9.15) — a reward model is a card (scorer + a score loop emitting
   REWARD_BATCH units); ServedRewardScorer drop-in-replaces the numpy scorer so any RL method becomes
   RLHF/RLAIF with no method change. ToyRewardModel; models/reward/. 4 tests.

#7 Content-adaptive control flow (§9.12) — CacheDiTDenoiseLoop (isolated WanDenoiseLoop subclass)
   reuses the cached velocity when predictions barely change (cache-dit skip) and early-exits on
   convergence — variable step count; interleave parity holds across ragged loops. models/adaptive/. 4 tests.

#8a Nested workflows (§9.13) — a workflow stage can invoke another workflow (engine.run routes ids);
   requires/validate recurse; cycles caught at registration + a run-time guard (engine._wf_running).
   build_t2i_i2v_extend_workflow. 5 tests.

designv4 §9.11–§9.15 + falsifier/layout/closing updates (148 tests, 25 files). Also removed a
pre-existing unused import in ltx2/loop.py.
2026-07-04 17:15:34 +00:00

71 lines
3.1 KiB
Python

"""Content-adaptive control flow — the loop owns it (design_v3 §2.2, §9.12).
Because the model owns control flow (the driven loop), content-adaptive compute is natural: the
`CacheDiTDenoiseLoop`'s `next()` reuses the cached velocity when consecutive predictions barely change
(cache-dit / TeaCache — skip the DiT forward), and early-exits when the latent converges — a variable,
content-dependent step count. These assert: skips happen and stay close to the full run; early-exit
reduces steps; and the interleave parity gate still holds across requests with *different* step counts.
"""
from __future__ import annotations
import numpy as np
from v2.cache import CacheManager
from v2.card import load_card
from v2.models import build_wan_t2v_program
from v2.models.adaptive import build_adaptive_card
from v2.parity import assert_interleave_parity
from v2.request import DiffusionParams, TaskType, make_request
from v2.runtime import Engine
STEPS = 12
def _engine(*, cache_threshold=0.0, exit_threshold=0.0):
card = build_adaptive_card(cache_threshold=cache_threshold, exit_threshold=exit_threshold)
inst = load_card(card, cache_manager=CacheManager.from_card(card))
eng = Engine()
eng.register(card.model_id, inst, build_wan_t2v_program())
return eng
def _run(eng, prompt="a calm sea", seed=3):
return eng.run(make_request(TaskType.T2V, "wan-adaptive", prompt,
diffusion=DiffusionParams(num_steps=STEPS, seed=seed)))
def test_threshold_zero_is_plain_denoise():
out = _run(_engine(cache_threshold=0.0))
assert out.metrics["denoise_steps"] == float(STEPS)
assert out.metrics["skipped_steps"] == 0.0 # subclass with threshold 0 ⇒ identical to base
def test_cache_dit_skips_forwards_and_stays_close():
full = _run(_engine(cache_threshold=0.0))
cached = _run(_engine(cache_threshold=0.15))
assert cached.metrics["skipped_steps"] > 0 # the loop chose to skip DiT forwards
v_full = np.asarray(full.artifacts["video"].frames)
v_cached = np.asarray(cached.artifacts["video"].frames)
rel = float(np.linalg.norm(v_cached - v_full) / (np.linalg.norm(v_full) + 1e-8))
assert rel < 0.05 # skipping is a close approximation, not exact
def test_early_exit_reduces_steps_in_the_tail():
eng = _engine(exit_threshold=0.05)
out = _run(eng)
assert out.metrics["early_exited"] == 1.0
assert out.metrics["denoise_steps"] < float(STEPS) # stopped before the full schedule
assert out.metrics["denoise_steps"] >= STEPS // 2 # ...but only in the low-noise tail, not at step 0
def test_interleave_parity_holds_with_variable_step_counts():
"""Different prompts skip/exit at different steps ⇒ ragged loops; serial == interleaved still."""
eng = _engine(cache_threshold=0.15)
reqs = [_make("alpha", 1), _make("beta gamma", 2), _make("alpha", 1)]
assert not assert_interleave_parity(eng, reqs)
def _make(prompt, seed):
return make_request(TaskType.T2V, "wan-adaptive", prompt,
diffusion=DiffusionParams(num_steps=STEPS, seed=seed))