unsloth/studio/backend/tests/test_diffusion_vae_quant.py
Daniel Han 6e2e8c846c Harden video diffusion cache, CFG-parallel replica, and layerwise-fp8 rollback
- diffusion_attention: clear the HunyuanVideo-1.5 null-mask flag with an always_call
  post-hook so it is scoped to one hooked forward and never latches across an
  exception; add attention_backend_supported_on_device to arch-gate an
  already-resolved backend on a specific (heterogeneous) CUDA device.
- video: make the explicit MagCache resize transactional via _step_cache_all_or_none
  (refuse to stack a fresh cache over one that could not be disabled; roll a mixed
  resize back and report the true state); raise on a failed all-or-none rollback
  instead of falsely reporting an uncached pipeline.
- diffusion_cfg_parallel: re-validate the attention backend on the replica device
  and pin native there when unsupported; mirror the primary's max tier on the
  replica (max-autotune compile + direct QKV fusion) via a new speed_mode arg;
  prefer a viable heterogeneous secondary GPU over an unusable identical one; clear
  the const cache at each plan_generation.
- diffusion_vae_quant / diffusion_precision: detect a partial diffusers
  layerwise-fp8 mutation (leftover casting hooks the torchao detector cannot see)
  and fail the load closed, while a clean failure still falls back to dense.
- video_speedmem_bench: engage the dual-expert cache all-or-none like the loader.
- frontend video api: add text_encoder_quant / vae_quant and the auto/off literals
  to VideoLoadRequest so typed callers match the backend contract.
2026-07-13 01:30:22 +00:00

627 lines
28 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
"""Unit tests for VAE quantisation (``diffusion_vae_quant.py``).
Hermetic: torch + the diffusers / torchao casters are stubbed via ``sys.modules`` so
gating, the conv filter, and the apply path run without a GPU, real diffusers, or real
torchao. Mirrors tests/test_diffusion_precision.py's stubbing style.
"""
from __future__ import annotations
import sys
import types
import pytest
import core.inference.diffusion_vae_quant as vq
from core.inference.diffusion_vae_quant import (
VAE_QUANT_AUTO,
VAE_QUANT_FP8,
VAE_QUANT_FP8_DYNAMIC,
_cast_vae_fp8,
_cast_vae_fp8_dynamic,
normalize_vae_quant,
quantize_vae,
select_vae_quant_scheme,
vae_quant_supported,
)
def _target(
*,
device = "cuda",
dtype = "bfloat16",
cc = (10, 0),
):
return types.SimpleNamespace(device = device, dtype = dtype, _cc = cc)
class _Weight:
"""A stand-in for a conv / linear weight tensor: exposes ``.shape`` and ``.dim()``."""
def __init__(self, shape):
self.shape = shape
def dim(self):
return len(self.shape)
def _stub_torch(
monkeypatch,
*,
with_fp8 = True,
cc = (10, 0),
):
torch = types.ModuleType("torch")
torch.bfloat16 = "bfloat16"
torch.float16 = "float16"
if with_fp8:
torch.float8_e4m3fn = "float8_e4m3fn"
# The conv filter isinstance-checks nn.Linear / nn.Conv2d / nn.Conv3d, and the layerwise
# caster reads torch.float8_e4m3fn, so the stub torch must expose both.
torch.nn = types.SimpleNamespace(
Linear = type("Linear", (), {}),
Conv2d = type("Conv2d", (), {}),
Conv3d = type("Conv3d", (), {}),
)
torch.cuda = types.SimpleNamespace(
get_device_capability = lambda *a: cc,
synchronize = lambda *a, **k: None,
is_available = lambda: True,
)
monkeypatch.setitem(sys.modules, "torch", torch)
return torch
def _stub_torchao(monkeypatch, captured):
# torchao's fp8_dynamic conv config + quantize_. Records the (config, filter_fn) so the
# PerTensor granularity and the conv filter closure can be asserted.
tq = types.ModuleType("torchao.quantization")
tq.quantize_ = lambda module, config, filter_fn = None: captured.update(
module = module, config = config, filter_fn = filter_fn
)
tq.Float8DynamicActivationFloat8WeightConfig = lambda granularity = None: ("fp8dyn", granularity)
tq.PerTensor = lambda: "pertensor"
monkeypatch.setitem(sys.modules, "torchao.quantization", tq)
return tq
def _stub_diffusers(monkeypatch, recorder):
hooks = types.ModuleType("diffusers.hooks")
casting = types.ModuleType("diffusers.hooks.layerwise_casting")
casting.DEFAULT_SKIP_MODULES_PATTERN = ("norm",)
hooks.apply_layerwise_casting = lambda module, **kw: recorder.append(("fp8", module, kw))
monkeypatch.setitem(sys.modules, "diffusers.hooks", hooks)
monkeypatch.setitem(sys.modules, "diffusers.hooks.layerwise_casting", casting)
def _stub_capability(monkeypatch, cc):
"""Stub the transformer module's ``_capability`` that select_vae_quant_scheme imports."""
dtq = types.ModuleType("core.inference.diffusion_transformer_quant")
dtq._capability = lambda: cc
monkeypatch.setitem(sys.modules, "core.inference.diffusion_transformer_quant", dtq)
return dtq
def _allow_vae(monkeypatch, allowed):
"""Force vae_quant_supported to accept only ``allowed`` (simulates the hardware gate)."""
monkeypatch.setattr(vq, "vae_quant_supported", lambda target, mode: mode in allowed)
# ── normalisation ─────────────────────────────────────────────────────────────
def test_normalize_vae_quant():
assert normalize_vae_quant(None) is None
assert normalize_vae_quant("") is None
assert normalize_vae_quant("none") is None
# "off" disables (like the TE / transformer normalisers) -> dense.
assert normalize_vae_quant("off") is None
# "auto" passes through for select_vae_quant_scheme to resolve.
assert normalize_vae_quant("AUTO") == VAE_QUANT_AUTO
assert normalize_vae_quant("FP8") == VAE_QUANT_FP8
# Hyphens fold to underscores so "fp8-dynamic" is accepted.
assert normalize_vae_quant("FP8-Dynamic") == VAE_QUANT_FP8_DYNAMIC
# int8 / nvfp4 have no VAE scheme -> rejected.
with pytest.raises(ValueError):
normalize_vae_quant("int8")
with pytest.raises(ValueError):
normalize_vae_quant("nvfp4")
# ── gating ────────────────────────────────────────────────────────────────────
def test_vae_quant_supported_fp8_requires_cuda_bf16_and_fp8(monkeypatch):
_stub_torch(monkeypatch, with_fp8 = True, cc = (8, 9))
assert vae_quant_supported(_target(), VAE_QUANT_FP8) is True
assert vae_quant_supported(_target(device = "cpu"), VAE_QUANT_FP8) is False
assert vae_quant_supported(_target(dtype = "float16"), VAE_QUANT_FP8) is False
# No fp8 dtype at all -> unsupported.
_stub_torch(monkeypatch, with_fp8 = False, cc = (8, 9))
assert vae_quant_supported(_target(), VAE_QUANT_FP8) is False
def test_vae_quant_supported_fp8_dynamic_requires_sm89(monkeypatch):
# Compute fp8 conv (torch._scaled_mm) needs fp8-GEMM silicon: Ada sm_89+ / Hopper / Blackwell.
_stub_torch(monkeypatch, cc = (8, 9))
assert vae_quant_supported(_target(), VAE_QUANT_FP8_DYNAMIC) is True
_stub_torch(monkeypatch, cc = (9, 0))
assert vae_quant_supported(_target(), VAE_QUANT_FP8_DYNAMIC) is True
# Ampere (8.0) has no fp8 GEMM.
_stub_torch(monkeypatch, cc = (8, 0))
assert vae_quant_supported(_target(), VAE_QUANT_FP8_DYNAMIC) is False
# ── auto ladder (select_vae_quant_scheme) ───────────────────────────────────────
def test_select_datacenter_uses_layerwise_fp8(monkeypatch):
# ``auto`` engages layerwise fp8 ONLY (fp8_dynamic is out of the auto ladder). Even on
# fp8-GEMM silicon it resolves to fp8, and the fp8_dynamic conv probe is never consulted.
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(
vq, "_vae_fp8_dynamic_probe", lambda *a: pytest.fail("auto must not probe fp8_dynamic")
)
assert select_vae_quant_scheme(_target(), "auto", family = "flux.1") == VAE_QUANT_FP8
def test_select_offload_uses_layerwise_fp8(monkeypatch):
# Under offload ``auto`` still resolves to layerwise fp8 (the storage-only scheme that
# survives Module.to()); the fp8_dynamic conv probe is never consulted.
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(
vq, "_vae_fp8_dynamic_probe", lambda *a: pytest.fail("probe must not run under offload")
)
assert select_vae_quant_scheme(_target(), "auto", offload_active = True) == VAE_QUANT_FP8
def test_select_force_fp32_stays_dense(monkeypatch):
# A force-fp32 (Wan) family never quantises, for auto or an explicit request.
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
assert select_vae_quant_scheme(_target(), "auto", force_fp32 = True) is None
assert select_vae_quant_scheme(_target(), "fp8", force_fp32 = True) is None
def test_select_family_deny_skips_scheme(monkeypatch):
# The only scheme ``auto`` walks is layerwise fp8, so denying fp8 for a family leaves it
# dense (None). (This is the SDXL case in the real deny list: fp8 marginal -> stay dense.)
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(vq, "_vae_fp8_dynamic_probe", lambda device, ndim = 2: True)
monkeypatch.setattr(vq, "_VAE_FAMILY_SCHEME_DENY", {"badfam": frozenset({VAE_QUANT_FP8})})
assert select_vae_quant_scheme(_target(), "auto", family = "badfam") is None
def test_select_no_capability_is_none(monkeypatch):
_stub_capability(monkeypatch, None)
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
assert select_vae_quant_scheme(_target(), "auto") is None
def test_select_support_gate_uses_fp8(monkeypatch):
# fp8-capable silicon with fp8 supported -> ``auto`` resolves to layerwise fp8.
_stub_capability(monkeypatch, (8, 9))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
assert select_vae_quant_scheme(_target(), "auto") == VAE_QUANT_FP8
def test_select_auto_never_uses_fp8_dynamic(monkeypatch):
# Even with fp8_dynamic hardware-supported and its conv probe passing, ``auto`` stays on
# layerwise fp8: fp8_dynamic is deliberately kept out of the auto ladder (explicit opt-in).
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(vq, "_vae_fp8_dynamic_probe", lambda device, ndim = 2: True)
assert select_vae_quant_scheme(_target(), "auto") == VAE_QUANT_FP8
def test_select_explicit_passthrough(monkeypatch):
# An explicit request is returned as-is (quantize_vae re-gates it); no ladder walk,
# so no transformer-module stub is needed.
assert select_vae_quant_scheme(_target(), "fp8") == VAE_QUANT_FP8
assert select_vae_quant_scheme(_target(), "fp8_dynamic") == VAE_QUANT_FP8_DYNAMIC
assert select_vae_quant_scheme(_target(), None) is None
assert select_vae_quant_scheme(_target(), "none") is None
def test_select_explicit_family_deny_returns_none(monkeypatch):
monkeypatch.setattr(vq, "_VAE_FAMILY_SCHEME_DENY", {"badfam": frozenset({VAE_QUANT_FP8})})
assert select_vae_quant_scheme(_target(), "fp8", family = "badfam") is None
# ── conv-aware filter (_cast_vae_fp8_dynamic) ───────────────────────────────────
def test_fp8_dynamic_conv_filter(monkeypatch):
# The real filter closure the PerTensor fp8 conv config receives: %16-channel Conv2d/Conv3d
# and Linear quantise; off-%16 channels and the conv_out / norm_out head stay dense.
torch = _stub_torch(monkeypatch)
captured: dict = {}
_stub_torchao(monkeypatch, captured)
_cast_vae_fp8_dynamic(object(), _target())
# PerTensor granularity (NOT the DiT's per-row) is what the config was built with.
assert captured["config"] == ("fp8dyn", "pertensor")
ff = captured["filter_fn"]
nn = torch.nn
def _mod(
cls,
shape,
kernel_size = None,
):
m = cls()
m.weight = _Weight(shape)
if kernel_size is not None:
m.kernel_size = kernel_size
return m
# Conv2d (4D) / Conv3d (5D) with both channel dims a multiple of 16 quantise.
assert ff(_mod(nn.Conv2d, (128, 128, 3, 3), (3, 3)), "decoder.up.0.resnets.0.conv1") is True
assert ff(_mod(nn.Conv3d, (64, 64, 3, 3, 3), (3, 3, 3)), "decoder.mid_block.conv3d") is True
# nn.Linear (mid-block attention projections) also quantise (no kernel_size attr).
assert ff(_mod(nn.Linear, (512, 512)), "decoder.mid_block.attentions.0.to_q") is True
# POINTWISE (1x1 / 1x1x1) convs excluded even at %16 channels: torchao 0.17's fp8 conv
# kernel rejects them ("Activation and filter channels must match") -> crash at decode.
assert (
ff(_mod(nn.Conv2d, (128, 128, 1, 1), (1, 1)), "decoder.mid_block.attentions.0.proj_conv")
is False
)
assert ff(_mod(nn.Conv3d, (64, 64, 1, 1, 1), (1, 1, 1)), "decoder.time_mix.conv") is False
# Channels not a multiple of 16 excluded (torchao would skip them regardless): the RGB
# in/out head (C=3) and any off-16 dim.
assert ff(_mod(nn.Conv2d, (128, 3, 3, 3), (3, 3)), "encoder.conv_in") is False
assert ff(_mod(nn.Conv2d, (24, 128, 3, 3), (3, 3)), "decoder.up.1.upsamplers.0.conv") is False
# conv_out / proj_out / norm_out excluded by NAME even with %16 channels.
assert ff(_mod(nn.Conv2d, (16, 128, 3, 3)), "decoder.conv_out") is False
assert ff(_mod(nn.Conv2d, (128, 128, 3, 3)), "decoder.conv_norm_out") is False
assert ff(_mod(nn.Conv2d, (128, 128, 3, 3)), "decoder.norm_out.conv") is False
assert ff(_mod(nn.Linear, (512, 512)), "decoder.proj_out") is False
# A non-conv/linear module (e.g. a GroupNorm) is excluded outright.
class _GroupNorm:
pass
gn = _GroupNorm()
gn.weight = _Weight((128,))
assert ff(gn, "decoder.mid_block.resnets.0.norm1") is False
# A weight with dim() < 2 (a 1D param) is excluded.
assert ff(_mod(nn.Conv2d, (128,)), "decoder.some.bias_only") is False
def test_cast_vae_fp8_layerwise_skips_head_and_norms(monkeypatch):
# The layerwise storage cast passes the decoder head + norm tokens through to diffusers'
# skip_modules_pattern (on top of the diffusers default), so they stay dense.
_stub_torch(monkeypatch)
recorder: list = []
_stub_diffusers(monkeypatch, recorder)
vae = object()
_cast_vae_fp8(vae, _target())
assert len(recorder) == 1
_, mod, kw = recorder[0]
assert mod is vae
assert kw["storage_dtype"] == "float8_e4m3fn"
assert kw["compute_dtype"] == "bfloat16"
skip = kw["skip_modules_pattern"]
# The diffusers default is preserved and the keep-dense tokens are appended.
assert "norm" in skip
for tok in ("conv_out", "proj_out", "conv_norm_out", "norm_out"):
assert tok in skip
# ── apply (quantize_vae) ────────────────────────────────────────────────────────
def test_quantize_vae_disabled_returns_none(monkeypatch):
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = None) is None
assert quantize_vae(pipe, _target(), mode = "none") is None
def test_quantize_vae_force_fp32_stays_dense(monkeypatch):
# A force-fp32 (Wan) family never casts, for an explicit scheme or auto.
_stub_torch(monkeypatch, cc = (10, 0))
monkeypatch.setattr(vq, "_cast_vae_fp8_dynamic", lambda v, t: pytest.fail("must not cast"))
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: pytest.fail("must not cast"))
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "fp8", force_fp32 = True) is None
assert quantize_vae(pipe, _target(), mode = "auto", force_fp32 = True) is None
def test_quantize_vae_offload_skips_fp8_dynamic(monkeypatch):
# Explicit fp8_dynamic under offload is skipped (torchao tensors reject Module.to());
# layerwise fp8 still engages.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(
vq, "_cast_vae_fp8_dynamic", lambda v, t: pytest.fail("torchao must not run under offload")
)
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "fp8_dynamic", offload_active = True) is None
fp8_calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: fp8_calls.append(v))
assert quantize_vae(pipe, _target(), mode = "fp8", offload_active = True) == VAE_QUANT_FP8
assert len(fp8_calls) == 1
def test_quantize_vae_unsupported_hw_is_noop(monkeypatch):
# An explicit scheme on hardware that does not support it applies nothing.
_stub_torch(monkeypatch, cc = (8, 0))
_allow_vae(monkeypatch, set())
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: pytest.fail("must not cast"))
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "fp8") is None
def test_quantize_vae_none_vae_is_noop(monkeypatch):
# A pipeline with no VAE attribute is a best-effort no-op even when the mode is supported.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
pipe = types.SimpleNamespace() # no .vae
assert quantize_vae(pipe, _target(), mode = "fp8") is None
def test_quantize_vae_explicit_fp8_applies(monkeypatch):
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: calls.append(v))
vae = object()
pipe = types.SimpleNamespace(vae = vae)
assert quantize_vae(pipe, _target(), mode = "fp8") == VAE_QUANT_FP8
assert calls == [vae]
def test_quantize_vae_tolerates_caster_failure(monkeypatch):
# The caster raising leaves the VAE dense (best-effort) -> None.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
def _boom(v, t):
raise RuntimeError("fp8 unsupported for this layer")
monkeypatch.setattr(vq, "_cast_vae_fp8", _boom)
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "fp8") is None
def test_quantize_vae_auto_resolves_and_applies(monkeypatch):
# End-to-end: mode="auto" resolves via the ladder (layerwise fp8) then applies that caster.
_stub_torch(monkeypatch, cc = (10, 0))
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(
vq, "_cast_vae_fp8_dynamic", lambda v, t: pytest.fail("auto must not use fp8_dynamic")
)
calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: calls.append(v))
vae = object()
pipe = types.SimpleNamespace(vae = vae)
# large VAE -> clears the size gate
monkeypatch.setattr(vq, "_vae_param_bytes", lambda v: 3_000_000_000)
assert quantize_vae(pipe, _target(), mode = "auto", family = "flux.1") == VAE_QUANT_FP8
assert calls == [vae]
def test_quantize_vae_auto_size_gate_skips_small(monkeypatch):
# auto leaves a small (image) VAE dense: halving ~0.2GB saves ~nothing and only slows decode.
_stub_torch(monkeypatch, cc = (10, 0))
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(vq, "_vae_param_bytes", lambda v: 200_000_000) # ~0.2 GB image VAE
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: pytest.fail("small VAE must stay dense"))
monkeypatch.setattr(
vq, "_cast_vae_fp8_dynamic", lambda v, t: pytest.fail("small VAE must stay dense")
)
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "auto", family = "flux.1") is None
def test_quantize_vae_auto_size_gate_allows_large(monkeypatch):
# auto quantises a large (video Conv3d) VAE: halving ~2.5GB saves ~1.2GB at ~2% decode.
_stub_torch(monkeypatch, cc = (10, 0))
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(vq, "_vae_param_bytes", lambda v: 2_500_000_000) # ~2.5 GB video VAE
calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: calls.append(v))
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "auto", family = "hunyuanvideo-1.5") == VAE_QUANT_FP8
assert len(calls) == 1
def test_quantize_vae_explicit_bypasses_size_gate(monkeypatch):
# An explicit request quantises even a small VAE -- the user opted in directly.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
monkeypatch.setattr(vq, "_vae_param_bytes", lambda v: 200_000_000) # small, but explicit
calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8", lambda v, t: calls.append(v))
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "fp8", family = "flux.1") == VAE_QUANT_FP8
assert len(calls) == 1
def test_quantize_vae_explicit_fp8_dynamic_probe_gates(monkeypatch):
# An explicit fp8_dynamic request runs the conv smoke probe: a build whose torchao lacks a
# working fp8 conv path (probe False) stays dense; a passing probe applies the caster.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
monkeypatch.setattr(vq, "_vae_fp8_dynamic_probe", lambda device, ndim = 2: False)
monkeypatch.setattr(
vq, "_cast_vae_fp8_dynamic", lambda v, t: pytest.fail("probe failed: must not cast")
)
pipe = types.SimpleNamespace(vae = object())
assert quantize_vae(pipe, _target(), mode = "fp8_dynamic", family = "flux.2-klein") is None
monkeypatch.setattr(vq, "_vae_fp8_dynamic_probe", lambda device, ndim = 2: True)
calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8_dynamic", lambda v, t: calls.append(v))
assert (
quantize_vae(pipe, _target(), mode = "fp8_dynamic", family = "flux.2-klein")
== VAE_QUANT_FP8_DYNAMIC
)
assert len(calls) == 1
def test_real_family_deny_list_policy(monkeypatch):
# The shipped _VAE_FAMILY_SCHEME_DENY (from the B200 sweep), exercised through the real
# select path -- no deny-list monkeypatch. Confirms the per-family auto/explicit outcomes.
_stub_capability(monkeypatch, (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
# SDXL denies BOTH schemes -> auto stays dense (its layerwise fp8 was marginal).
assert select_vae_quant_scheme(_target(), "auto", family = "sdxl") is None
assert select_vae_quant_scheme(_target(), "fp8", family = "sdxl") is None
# Qwen-Image: auto -> layerwise fp8 (safe); explicit fp8_dynamic refused (catastrophic).
assert select_vae_quant_scheme(_target(), "auto", family = "qwen-image") == VAE_QUANT_FP8
assert select_vae_quant_scheme(_target(), "fp8_dynamic", family = "qwen-image") is None
# FLUX.1 / LTX-2 keep layerwise fp8 on auto but deny explicit fp8_dynamic.
assert select_vae_quant_scheme(_target(), "auto", family = "ltx-2") == VAE_QUANT_FP8
assert select_vae_quant_scheme(_target(), "fp8_dynamic", family = "flux.1") is None
# FLUX.2 / Hunyuan keep fp8_dynamic available as an explicit opt-in (measured in-bar).
assert (
select_vae_quant_scheme(_target(), "fp8_dynamic", family = "flux.2-klein")
== VAE_QUANT_FP8_DYNAMIC
)
assert (
select_vae_quant_scheme(_target(), "fp8_dynamic", family = "hunyuanvideo-1.5")
== VAE_QUANT_FP8_DYNAMIC
)
# ── conv-dimensionality probe gating ─────────────────────────────────────────────
def _conv_vae(torch, *ndims):
"""A fake VAE whose .modules() yields stub Conv2d/Conv3d instances for ``ndims``."""
mods = [(torch.nn.Conv3d if n == 3 else torch.nn.Conv2d)() for n in ndims]
return types.SimpleNamespace(modules = lambda: iter(mods))
def test_vae_conv_ndims(monkeypatch):
torch = _stub_torch(monkeypatch)
assert vq._vae_conv_ndims(_conv_vae(torch, 2)) == (2,)
assert vq._vae_conv_ndims(_conv_vae(torch, 3)) == (3,)
assert vq._vae_conv_ndims(_conv_vae(torch, 2, 3)) == (2, 3)
# A VAE that cannot be inspected (no .modules()) falls back to the 2D probe.
assert vq._vae_conv_ndims(object()) == (2,)
def test_quantize_vae_fp8_dynamic_probes_conv3d_for_video_vae(monkeypatch):
# A Conv3d (video) VAE must pass the 3D conv probe: a build whose Conv2d path works but
# Conv3d is broken would else crash at the first decode. Probe ok for 2D but not 3D -> dense.
torch = _stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8_DYNAMIC, VAE_QUANT_FP8})
probed: list = []
def _probe(device, ndim = 2):
probed.append(ndim)
return ndim == 2
monkeypatch.setattr(vq, "_vae_fp8_dynamic_probe", _probe)
monkeypatch.setattr(
vq, "_cast_vae_fp8_dynamic", lambda v, t: pytest.fail("3D probe failed: must not cast")
)
pipe = types.SimpleNamespace(vae = _conv_vae(torch, 2, 3))
assert quantize_vae(pipe, _target(), mode = "fp8_dynamic", family = "hunyuanvideo-1.5") is None
assert 3 in probed
# A build whose 3D path also works casts the video VAE.
monkeypatch.setattr(vq, "_vae_fp8_dynamic_probe", lambda device, ndim = 2: True)
pipe = types.SimpleNamespace(vae = _conv_vae(torch, 2, 3))
calls: list = []
monkeypatch.setattr(vq, "_cast_vae_fp8_dynamic", lambda v, t: calls.append(v))
assert (
quantize_vae(pipe, _target(), mode = "fp8_dynamic", family = "hunyuanvideo-1.5")
== VAE_QUANT_FP8_DYNAMIC
)
assert len(calls) == 1
# ── partial in-place quant detection (fails the load, not a silent dense report) ───
class _TorchaoLikeTensor:
"""Detection keys on the tensor class's module path ("torchao" in __module__)."""
_TorchaoLikeTensor.__module__ = "torchao.dtypes.affine_quantized_tensor"
class _PartiallyQuantizedVae:
def __init__(self):
self._swapped = False
def named_parameters(self):
if self._swapped:
yield ("decoder.up_blocks.0.conv.weight", _TorchaoLikeTensor())
yield ("decoder.up_blocks.1.conv.weight", types.SimpleNamespace())
def test_quantize_vae_partial_cast_failure_fails_load(monkeypatch):
# fp8_dynamic's quantize_ swaps weights module-by-module: a mid-pass failure that left
# torchao params behind must raise instead of reporting a dense fallback.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
def _swap_one_then_boom(v, t):
v._swapped = True
raise RuntimeError("mid-pass conv failure")
monkeypatch.setattr(vq, "_cast_vae_fp8", _swap_one_then_boom)
pipe = types.SimpleNamespace(vae = _PartiallyQuantizedVae())
with pytest.raises(RuntimeError, match = "partially quantized"):
quantize_vae(pipe, _target(), mode = "fp8")
# ── layerwise fp8 partial mutation (torchao detector is blind to diffusers hooks) ──
class _LayerwiseCastVae:
"""A VAE an apply_layerwise_casting pass mutated (installed an fp8-storage upcast hook on a
submodule) before the caster raised. It carries NO torchao params, so raise_if_partially_
quantized would miss the partial state -- _has_layerwise_casting must catch it."""
def __init__(self):
registry = types.SimpleNamespace(
get_hook = lambda name: object() if name == "layerwise_casting" else None
)
self._sub = types.SimpleNamespace(_diffusers_hook = registry)
def modules(self):
return [self, self._sub]
def named_parameters(self):
return iter(())
def test_quantize_vae_layerwise_partial_cast_fails_load(monkeypatch):
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
def _boom(v, t):
raise RuntimeError("layerwise casting failed mid-pass")
monkeypatch.setattr(vq, "_cast_vae_fp8", _boom)
pipe = types.SimpleNamespace(vae = _LayerwiseCastVae())
with pytest.raises(RuntimeError, match = "leftover fp8 hooks"):
quantize_vae(pipe, _target(), mode = "fp8")
def test_quantize_vae_clean_layerwise_failure_stays_dense(monkeypatch):
# A failure with NO leftover hook (raised before mutating anything) still falls back to dense,
# preserving the storage-only fp8 contract -- the fail-closed path is scoped to real mutation.
_stub_torch(monkeypatch, cc = (10, 0))
_allow_vae(monkeypatch, {VAE_QUANT_FP8})
class _CleanVae:
def modules(self):
return [self]
def named_parameters(self):
return iter(())
def _boom(v, t):
raise RuntimeError("fp8 unsupported before any mutation")
monkeypatch.setattr(vq, "_cast_vae_fp8", _boom)
pipe = types.SimpleNamespace(vae = _CleanVae())
assert quantize_vae(pipe, _target(), mode = "fp8") is None