wan-vae: rework causal padding

This currently uses F.pad which takes a full deep copy and is liable to
be the VRAM peak. Instead, kick spatial padding back to the op and
consolidate the temporal padding with the cat for the cache.
This commit is contained in:
Rattus 2026-01-23 12:06:36 +10:00
parent 70b20d14cd
commit 613eee564b

View File

@ -5,7 +5,7 @@ import torch
import torch.nn as nn
import torch.nn.functional as F
from einops import rearrange
from comfy.ldm.modules.diffusionmodules.model import vae_attention
from comfy.ldm.modules.diffusionmodules.model import vae_attention, torch_cat_if_needed
import comfy.ops
ops = comfy.ops.disable_weight_init
@ -20,22 +20,24 @@ class CausalConv3d(ops.Conv3d):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self._padding = (self.padding[2], self.padding[2], self.padding[1],
self.padding[1], 2 * self.padding[0], 0)
self.padding = (0, 0, 0)
self._padding = 2 * self.padding[0]
self.padding = (0, self.padding[1], self.padding[2])
def forward(self, x, cache_x=None, cache_list=None, cache_idx=None):
if cache_list is not None:
cache_x = cache_list[cache_idx]
cache_list[cache_idx] = None
padding = list(self._padding)
if cache_x is not None and self._padding[4] > 0:
cache_x = cache_x.to(x.device)
x = torch.cat([cache_x, x], dim=2)
padding[4] -= cache_x.shape[2]
if self._padding > 0:
padding_needed = self._padding
if cache_x is not None:
cache_x = cache_x.to(x.device)
padding_needed = max(0, padding_needed - cache_x.shape[2])
padding_shape = list(x.shape)
padding_shape[2] = padding_needed
padding = torch.zeros(padding_shape, device=x.device, dtype=x.dtype)
x = torch_cat_if_needed([padding, cache_x, x], dim=2)
del cache_x
x = F.pad(x, padding)
return super().forward(x)