Adds is_float8_dtype() helper to detect any FP8 format (e4m3fn, e5m2, e4m3fnuz, e5m2fnuz) and automatically convert to FP16 when targeting devices without native FP8 support (< SM90).

This fixes compatibility with models like LTX-Video, Wan, and others that may use different FP8 encoding schemes (particularly e5m2) on mixed GPU setups.

Changes:
- Add is_float8_dtype() to detect all PyTorch FP8 variants
- Update clone_module_simple() to handle FP8 in layer reconstruction and generic fallback
- Update safe_model_clone() to post-process all FP8 variants during incremental loading
- Update move_to_device() to convert FP8 inputs at runtime during parallel inference
- Ensure consistent FP8→FP16 conversion across weights, buffers, and activation tensors

Preserves FP8 performance on Hopper/Ada (SM90+) while ensuring compatibility with Ampere and older architectures that only support FP16/FP32 computation.

Fixes: Support for LTX-Video, Wan, and other FP8 models using e5m2 or alternative FP8 formats on mixed-GPU setups
This commit is contained in:
FearL0rd
2026-02-07 11:54:14 -06:00
parent f74eae7e64
commit 0644b55d4b
2 changed files with 125 additions and 63 deletions
+124 -62
View File
@@ -9,6 +9,13 @@ from dataclasses import dataclass, fields, is_dataclass
from concurrent.futures import ThreadPoolExecutor, as_completed
import comfy.model_management
def is_float8_dtype(dtype):
"""Check if dtype is any FP8 variant (E4M3, E5M2, etc.)."""
if dtype is None:
return False
dtype_name = str(dtype)
fp8_types = ['float8_e4m3fn', 'float8_e5m2', 'float8_e4m3fnuz', 'float8_e5m2fnuz', 'float8']
return any(t in dtype_name for t in fp8_types)
def check_sm80_support(device_name):
"""Check if CUDA device supports SM_80 (Ampere) or higher."""
@@ -23,6 +30,21 @@ def check_sm80_support(device_name):
print(f"[ParallelAnything] Warning: Could not check compute capability for {device_name}: {e}")
return False
def device_supports_float8(device):
"""Check if CUDA device supports Float8 computation (SM90+ / Hopper/Ada)."""
if isinstance(device, str):
if not device.startswith("cuda"):
return False
device = torch.device(device)
if device.type != 'cuda':
return False
try:
cap = torch.cuda.get_device_capability(device)
major, minor = cap
# FP8 computation requires Hopper/Ada (SM9.0+) or newer
return (major, minor) >= (9, 0)
except:
return False
def disable_flash_xformers(model):
"""Aggressively disable Flash Attention and xFormers on the model."""
@@ -69,7 +91,6 @@ def disable_flash_xformers(model):
except Exception:
pass
def clear_flux_caches(model):
"""Clear FLUX-specific cached tensors that depend on batch size or input dimensions."""
cache_attrs = [
@@ -80,6 +101,7 @@ def clear_flux_caches(model):
'rope_cache', '_rope_cache', 'freqs_cis_cache', '_freqs_cis_cache',
'temporal_ids', 'frame_ids', 'video_ids', 'temp_pos_emb',
]
cleared_count = 0
def clear_attrs(obj, name_prefix=""):
@@ -103,7 +125,6 @@ def clear_flux_caches(model):
if cleared_count > 0:
print(f"[ParallelAnything] Cleared {cleared_count} cached tensors")
def aggressive_cleanup():
"""Force aggressive CUDA memory cleanup."""
gc.collect()
@@ -120,7 +141,6 @@ def aggressive_cleanup():
pass
comfy.model_management.soft_empty_cache()
def cleanup_parallel_model(model_ref):
"""Cleanup function to remove parallel replicas and restore original model."""
model = model_ref() if isinstance(model_ref, weakref.ref) else model_ref
@@ -161,6 +181,7 @@ def cleanup_parallel_model(model_ref):
replica._gradient_checkpointing_func = None
except Exception as e:
print(f"[ParallelAnything] Warning: Error cleaning up replica on {dev_name}: {e}")
try:
delattr(model, '_parallel_replicas')
except Exception:
@@ -203,20 +224,20 @@ def cleanup_parallel_model(model_ref):
except:
pass
def extract_model_config(model):
"""Extract initialization config from model instance with FLUX-specific handling."""
config = {}
possible_attrs = [
'in_channels', 'out_channels', 'vec_in_dim', 'context_in_dim', 'hidden_size',
'mlp_ratio', 'num_heads', 'depth', 'depth_single_blocks', 'depth_single',
'axes_dim', 'theta', 'patch_size', 'qkv_bias', 'guidance_embed',
'txt_ids_dim', 'img_ids_dim', 'num_res_blocks', 'attention_resolutions',
'dropout', 'channel_mult', 'num_classes', 'use_checkpoint', 'num_heads_upsample',
'use_scale_shift_norm', 'resblock_updown', 'use_new_attention_order',
'adm_in_channels', 'num_noises', 'context_dim', 'n_heads', 'd_head',
'transformer_depth', 'model_channels', 'max_depth', 'num_frames',
'temporal_compression', 'temporal_dim', 'video_length',
'dropout', 'channel_mult', 'num_classes', 'use_checkpoint',
'num_heads_upsample', 'use_scale_shift_norm', 'resblock_updown',
'use_new_attention_order', 'adm_in_channels', 'num_noises', 'context_dim',
'n_heads', 'd_head', 'transformer_depth', 'model_channels', 'max_depth',
'num_frames', 'temporal_compression', 'temporal_dim', 'video_length',
]
for attr in possible_attrs:
@@ -246,7 +267,7 @@ def extract_model_config(model):
params_dict = vars(params)
if params_dict:
config.update({k: v for k, v in params_dict.items()
if not isinstance(v, (torch.Tensor, nn.Module))})
if not isinstance(v, (torch.Tensor, nn.Module))})
except Exception:
pass
@@ -256,7 +277,7 @@ def extract_model_config(model):
cfg = model.config
if isinstance(cfg, dict):
config.update({k: v for k, v in cfg.items()
if not isinstance(v, (torch.Tensor, nn.Module))})
if not isinstance(v, (torch.Tensor, nn.Module))})
else:
cfg_dict = {k: v for k, v in vars(cfg).items()
if not k.startswith('_') and not callable(v)
@@ -281,7 +302,6 @@ def extract_model_config(model):
return clean_config
def clone_dataclass_or_object(obj, target_device=None):
"""Deep copy a dataclass or simple object, handling nested structures."""
if is_dataclass(obj):
@@ -317,14 +337,12 @@ def clone_dataclass_or_object(obj, target_device=None):
except Exception:
return obj
def safe_getattr(obj, attr, default=None):
"""Safely get attribute, returning default if not exists."""
return getattr(obj, attr, default)
def clone_module_simple(module, target_device):
"""Simple module cloning that handles Parameters and FLUX-specific attributes."""
"""Simple module cloning that handles Parameters and FLUX-specific attributes with FP8 support."""
if module is None:
return None
@@ -337,6 +355,11 @@ def clone_module_simple(module, target_device):
weight_dtype = weight.dtype if weight is not None else torch.float32
has_bias = safe_getattr(module, 'bias', None) is not None
# Check FP8 support for target device
supports_fp8 = device_supports_float8(target_device)
if not supports_fp8 and is_float8_dtype(weight_dtype):
weight_dtype = torch.float16
if isinstance(module, nn.Linear):
in_features = safe_getattr(module, 'in_features')
out_features = safe_getattr(module, 'out_features')
@@ -371,6 +394,9 @@ def clone_module_simple(module, target_device):
with torch.no_grad():
if weight is not None:
# Convert FP8 to FP16 if needed
if not supports_fp8 and is_float8_dtype(weight.dtype):
weight = weight.half()
new_mod.weight.copy_(weight)
if has_bias and safe_getattr(module, 'bias') is not None:
new_mod.bias.copy_(module.bias)
@@ -385,6 +411,11 @@ def clone_module_simple(module, target_device):
weight = safe_getattr(module, 'weight', None)
weight_dtype = weight.dtype if weight is not None else torch.float32
# Check FP8 support for target device
supports_fp8 = device_supports_float8(target_device)
if not supports_fp8 and is_float8_dtype(weight_dtype):
weight_dtype = torch.float16
if isinstance(module, nn.LayerNorm):
new_mod = nn.LayerNorm(
safe_getattr(module, 'normalized_shape'),
@@ -412,6 +443,8 @@ def clone_module_simple(module, target_device):
with torch.no_grad():
if weight is not None:
if not supports_fp8 and is_float8_dtype(weight.dtype):
weight = weight.half()
new_mod.weight.copy_(weight)
if safe_getattr(module, 'bias') is not None:
new_mod.bias.copy_(module.bias)
@@ -430,11 +463,17 @@ def clone_module_simple(module, target_device):
new_mod = module_class.__new__(module_class)
nn.Module.__init__(new_mod)
# Check if target supports FP8
supports_fp8 = device_supports_float8(target_device)
# Copy parameters
for name, param in module.named_parameters(recurse=False):
if param is not None:
new_param = nn.Parameter(param.clone().detach().to(device=target_device),
requires_grad=False)
new_param_data = param.clone().detach()
# Convert FP8 to FP16 for older GPUs
if not supports_fp8 and is_float8_dtype(new_param_data.dtype):
new_param_data = new_param_data.half()
new_param = nn.Parameter(new_param_data.to(device=target_device), requires_grad=False)
new_mod.register_parameter(name, new_param)
else:
new_mod.register_parameter(name, None)
@@ -442,7 +481,11 @@ def clone_module_simple(module, target_device):
# Copy buffers
for name, buffer in module.named_buffers(recurse=False):
if buffer is not None:
new_buffer = buffer.clone().detach().to(device=target_device)
new_buffer_data = buffer.clone().detach()
# Convert FP8 to FP16 for older GPUs
if not supports_fp8 and is_float8_dtype(new_buffer_data.dtype):
new_buffer_data = new_buffer_data.half()
new_buffer = new_buffer_data.to(device=target_device)
new_mod.register_buffer(name, new_buffer)
else:
new_mod.register_buffer(name, None)
@@ -477,12 +520,22 @@ def clone_module_simple(module, target_device):
if key in cache_attrs:
setattr(new_mod, key, None)
else:
setattr(new_mod, key, value.clone().detach().to(target_device))
tensor_val = value.clone().detach()
# Convert FP8 to FP16 if needed
if not supports_fp8 and is_float8_dtype(tensor_val.dtype):
tensor_val = tensor_val.half()
setattr(new_mod, key, tensor_val.to(target_device))
elif isinstance(value, (list, tuple)) and len(value) > 0 and isinstance(value[0], torch.Tensor):
if key in cache_attrs:
setattr(new_mod, key, None)
else:
setattr(new_mod, key, type(value)(t.clone().detach().to(target_device) for t in value))
converted = []
for t in value:
t_conv = t.clone().detach()
if not supports_fp8 and is_float8_dtype(t_conv.dtype):
t_conv = t_conv.half()
converted.append(t_conv.to(target_device))
setattr(new_mod, key, type(value)(converted))
else:
setattr(new_mod, key, copy.deepcopy(value))
except Exception:
@@ -492,9 +545,8 @@ def clone_module_simple(module, target_device):
except Exception as e:
raise RuntimeError(f"Failed to clone module {module_class}: {e}")
def safe_model_clone(source_model, target_device, disable_flash=False):
"""FLUX-safe model cloning with explicit memory cleanup."""
"""FLUX-safe model cloning with explicit memory cleanup and FP8 handling."""
clear_flux_caches(source_model)
# Determine source device
@@ -550,6 +602,8 @@ def safe_model_clone(source_model, target_device, disable_flash=False):
# Load state dict piece by piece to minimize memory spike
print(f"[ParallelAnything] Loading parameters incrementally...")
supports_fp8 = device_supports_float8(target_device)
with torch.no_grad():
for key in list(state_dict.keys()):
try:
@@ -565,17 +619,19 @@ def safe_model_clone(source_model, target_device, disable_flash=False):
target_param = getattr(replica, key)
if isinstance(target_param, (torch.nn.Parameter, torch.Tensor)):
# Load directly to target device
target_param.data.copy_(param.to(target_device, non_blocking=False))
# Delete immediately to free memory
del state_dict[key]
del param
# Periodic cleanup for very large models
if len(state_dict) % 50 == 0 and torch.cuda.is_available():
torch.cuda.empty_cache()
# Load directly to target device with FP8 handling
param_data = param.to(target_device, non_blocking=False)
if is_float8_dtype(param_data.dtype) and not supports_fp8:
param_data = param_data.half()
target_param.data.copy_(param_data)
# Delete immediately to free memory
del state_dict[key]
del param
# Periodic cleanup for very large models
if len(state_dict) % 50 == 0 and torch.cuda.is_available():
torch.cuda.empty_cache()
except Exception as e:
print(f"[ParallelAnything] Warning: Could not load {key}: {e}")
@@ -606,6 +662,20 @@ def safe_model_clone(source_model, target_device, disable_flash=False):
# Post-processing
clear_flux_caches(replica)
# CRITICAL FIX: Convert FP8 to FP16 for older GPUs after cloning
if not device_supports_float8(target_device):
print(f"[ParallelAnything] Converting FP8 weights to FP16 for {target_device}...")
def convert_fp8_recursive(m):
for name, param in m.named_parameters():
if is_float8_dtype(param.dtype):
param.data = param.data.half()
for name, buffer in m.named_buffers():
if is_float8_dtype(buffer.dtype):
buffer.data = buffer.data.half()
for child in m.children():
convert_fp8_recursive(child)
convert_fp8_recursive(replica)
# Disable gradient checkpointing to save VRAM
if hasattr(replica, 'gradient_checkpointing'):
replica.gradient_checkpointing = False
@@ -633,7 +703,6 @@ def safe_model_clone(source_model, target_device, disable_flash=False):
print(f"[ParallelAnything] Cloned via {method_used} to {target_device}")
return replica
def get_free_vram(device_name):
"""Get available VRAM in MB for a device."""
try:
@@ -641,13 +710,12 @@ def get_free_vram(device_name):
idx = int(device_name.split(":")[-1])
torch.cuda.set_device(idx)
free_memory = (torch.cuda.get_device_properties(idx).total_memory -
torch.cuda.memory_allocated(idx))
torch.cuda.memory_allocated(idx))
return free_memory / (1024 ** 2) # Convert to MB
except Exception:
pass
return 0
def auto_split_batch(batch_size, devices, weights):
"""Adjust split based on available VRAM."""
if not any(d.startswith("cuda") for d in devices):
@@ -679,11 +747,10 @@ def auto_split_batch(batch_size, devices, weights):
adjusted_weights = [w/total for w in adjusted_weights]
split_sizes = [max(1, int(batch_size * w)) for w in adjusted_weights]
split_sizes[-1] = batch_size - sum(split_sizes[:-1]) # Adjust last to ensure sum = batch_size
split_sizes[-1] = batch_size - sum(split_sizes[:-1]) # Ensure sum = batch_size
return split_sizes
class ParallelDevice:
@classmethod
def get_available_devices(cls):
@@ -703,7 +770,7 @@ class ParallelDevice:
except ImportError:
pass
return devices
@classmethod
def INPUT_TYPES(s):
available = s.get_available_devices()
@@ -734,7 +801,7 @@ class ParallelDevice:
FUNCTION = "add_device"
CATEGORY = "utils/hardware"
DESCRIPTION = "Add a GPU/CPU/MPS/XPU device to the parallel processing chain"
def add_device(self, device_id, percentage, previous_devices=None):
if previous_devices is None:
previous_devices = []
@@ -747,9 +814,9 @@ class ParallelDevice:
new_chain = previous_devices.copy()
new_chain.append(config)
return (new_chain,)
class ParallelDeviceList:
@classmethod
def get_available_devices(cls):
@@ -763,7 +830,7 @@ class ParallelDeviceList:
for i in range(torch.xpu.device_count()):
devices.append(f"xpu:{i}")
return devices
@classmethod
def INPUT_TYPES(s):
devices = s.get_available_devices()
@@ -787,10 +854,12 @@ class ParallelDeviceList:
RETURN_NAMES = ("device_chain",)
FUNCTION = "create_list"
CATEGORY = "utils/hardware"
def create_list(self, device_1, pct_1, device_2, pct_2, device_3="cpu", pct_3=0, device_4="cpu", pct_4=0):
def create_list(self, device_1, pct_1, device_2, pct_2,
device_3="cpu", pct_3=0, device_4="cpu", pct_4=0):
chain = []
devices = [(device_1, pct_1), (device_2, pct_2), (device_3, pct_3), (device_4, pct_4)]
devices = [(device_1, pct_1), (device_2, pct_2),
(device_3, pct_3), (device_4, pct_4)]
for dev_str, pct in devices:
if pct > 0:
@@ -802,7 +871,6 @@ class ParallelDeviceList:
return (chain,)
class ParallelAnything:
@classmethod
def INPUT_TYPES(s):
@@ -835,9 +903,9 @@ class ParallelAnything:
RETURN_NAMES = ("model",)
FUNCTION = "setup_parallel"
CATEGORY = "utils/hardware"
def setup_parallel(self, model, device_chain, workload_split=True, auto_vram_balance=False,
purge_cache=True, purge_models=False):
def setup_parallel(self, model, device_chain, workload_split=True,
auto_vram_balance=False, purge_cache=True, purge_models=False):
if model is None or not device_chain:
return (model,)
@@ -905,7 +973,6 @@ class ParallelAnything:
# Move original to CPU to free VRAM for cloning, unless it's the only device and matches
needs_cpu_transition = original_device.type == 'cuda' and original_device_str not in device_names
if needs_cpu_transition:
print(f"[ParallelAnything] Moving model to CPU for safe cloning...")
target_model = target_model.cpu()
@@ -938,8 +1005,8 @@ class ParallelAnything:
replica = safe_model_clone(target_model, dev, disable_flash=need_safe)
clear_flux_caches(replica)
replicas[dev_name] = replica
replicas[dev_name] = replica
if dev.type == 'cuda':
streams[dev_name] = torch.cuda.Stream(dev)
@@ -964,7 +1031,6 @@ class ParallelAnything:
raise RuntimeError("No devices available for parallel processing - all OOM")
print(f"[ParallelAnything] Reducing to {len(successful_devices)} devices due to OOM")
device_names = successful_devices
# Renormalize weights
total_weight = sum(successful_weights)
weights = [w/total_weight for w in successful_weights]
@@ -1046,11 +1112,14 @@ class ParallelAnything:
return [x] * len(split_sizes)
def move_to_device(x, device, non_blocking=False):
"""Move tensor or list/tuple of tensors to device."""
"""Move tensor or list/tuple of tensors to device with FP8 handling."""
if isinstance(x, torch.Tensor):
# Only move if not already on target device
if x.device != torch.device(device):
return x.to(device, non_blocking=non_blocking)
x = x.to(device, non_blocking=non_blocking)
# CRITICAL FIX: Convert FP8 to FP16 for old GPUs
if is_float8_dtype(x.dtype) and not device_supports_float8(device):
x = x.half()
return x
elif isinstance(x, (list, tuple)):
moved = [move_to_device(t, device, non_blocking) for t in x]
@@ -1072,9 +1141,6 @@ class ParallelAnything:
split_lists = [torch.split(t, split_sizes, dim=0) for t in value]
for i in range(len(split_sizes)):
split_kwargs_list[i][key] = type(value)(sl[i] for sl in split_lists)
else:
for i in range(len(split_sizes)):
split_kwargs_list[i][key] = value
else:
for i in range(len(split_sizes)):
split_kwargs_list[i][key] = value
@@ -1159,6 +1225,7 @@ class ParallelAnything:
c_chunks = split_batch(context, [a['size'] for a in active])
else:
c_chunks = [None] * len(active)
kwargs_chunks = split_kwargs(kwargs, [a['size'] for a in active], batch_size)
results = [None] * len(active)
@@ -1174,9 +1241,7 @@ class ParallelAnything:
# Move inputs to device
x_in = move_to_device(x_chunks[task_idx], dev)
t_in = move_to_device(t_chunks[task_idx], dev)
c_in = None
if c_chunks[task_idx] is not None:
c_in = move_to_device(c_chunks[task_idx], dev)
c_in = move_to_device(c_chunks[task_idx], dev) if c_chunks[task_idx] is not None else None
# Move kwargs
k_in = {}
@@ -1184,7 +1249,6 @@ class ParallelAnything:
k_in[k] = move_to_device(v, dev, non_blocking=False)
# CRITICAL FIX: Check if this is the original model to avoid recursion
# If replica has _original_forward, it means it's the patched model, so use that
if hasattr(replica, '_original_forward'):
forward_fn = replica._original_forward
else:
@@ -1250,7 +1314,6 @@ class ParallelAnything:
if "out of memory" in str(e).lower():
print("[ParallelAnything] OOM in parallel forward, attempting emergency cleanup...")
aggressive_cleanup()
# Try single device fallback on lead device
print("[ParallelAnything] Falling back to single device processing...")
with torch.no_grad():
@@ -1282,7 +1345,6 @@ class ParallelAnything:
print(f"[ParallelAnything] Parallel setup complete. Using devices: {device_names}")
return (model,)
NODE_CLASS_MAPPINGS = {
"ParallelAnything": ParallelAnything,
"ParallelDevice": ParallelDevice,
+1 -1
View File
@@ -2,7 +2,7 @@
[project]
name = "ComfyUI-ParallelAnything" # Unique identifier for your node. Immutable after creation.
description = "This suite of nodes unlocks high-performance parallel processing in ComfyUI by utilizing **Model Replication**. Unlike standard offloading which moves a single model instance between devices, these nodes create independent replicas of the model on each selected GPU/CPU, allowing for true simultaneous batch processing."
version = "1.0.6" # Custom Node version. Must be semantically versioned.
version = "1.0.7" # Custom Node version. Must be semantically versioned.
license = { file = "LICENSE.txt" }
dependencies = [] # Filled in from requirements.txt