Both qwen-zimage stages prompt with module constants, and at CFG 1.0 DiffSynth's
PipelineUnitRunner reuses the positive embedding for the negative side rather
than encoding it, so exactly one embedding per stage is ever computed. Persist it
and neither text encoder has to be loaded at all.
Measured on an H100 volume: this drops 15.45 GiB (Qwen2.5-VL) and 7.49 GiB
(Z-Image) of an 87.6 GiB per-request read, worth a median 11.76 s and 4.10 s of
load time paired within five containers. A nine-face fixture returned
sha256 c8567e11077de32a both with and without the cache, so the output is
byte-identical and the provider-oracle clearance is untouched.
The cache key carries the cache version, model id, pipeline output params and the
exact prompt, so a model bump or a prompt edit recomputes instead of reading a
stale embedding. The write is atomic because a torn file must never read back as
a hit, and a miss after the text encoder was already dropped raises rather than
calling a model that is not loaded.
_model_cache_dir now prefers HF_HOME: on a scale-to-zero runner that is the only
persistently mounted path, so anything below it is re-derived every request. The
YuNet download follows the same root.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Joins fix/qwen-vram-residency, which carried the global-stack residency
change on the v0.20.1 line that raiw-app pins. The change itself is already
on main via port/qwen-vram-residency-main, reapplied there because the
package layout moved under _internal/ in between, so this merge is history
only and its tree is identical to the commit before it.
Conflicts resolved in favour of main throughout, including dropping the
noai/watermark_remover.py the branch resurrected; that module now lives at
_internal/watermark_remover.py.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Port of the same change made on the v0.20.1 line, reapplied here because the
package layout moved under _internal/ in the meantime.
The mandatory Qwen stack was configured to offload to disk unconditionally.
DiffSynth implements that by dropping the weights to the meta device and
re-reading every parameter through its DiskMap on the next onload, and the
pipeline moves between text encoder, transformer and VAE on every pass, so
each generation paid a full model reload. That is the right trade on a
consumer card, where it is what makes a 20B model runnable at all, and pure
waste on a card that can simply hold the stack.
Residency is now resolved from total VRAM, mirroring how the optional
Z-Image face stack is already gated. Above the floor the config passes no
"disk" value anywhere, which is what actually disables the behavior:
DiffSynth latches disk_offload once from offload_dtype, so pointing every
device at CUDA while leaving the sentinel would keep both the meta-drop and
the re-read.
Measured on an H100: a warm global pass went from 37.3s at 0.8 GiB resident
to 2.2s at 28.7 GiB, with both stacks resident peaking at 48.0 GiB of 79.2.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The mandatory Qwen stack was configured to offload to disk unconditionally.
DiffSynth implements that by dropping the weights to the meta device and
re-reading every parameter through its DiskMap on the next onload, and the
pipeline moves between text encoder, transformer and VAE on every pass, so
each generation paid a full model reload. That is the right trade on a
consumer card, where it is what makes a 20B model runnable at all, and pure
waste on a card that can simply hold the stack.
Residency is now resolved from total VRAM, mirroring how the optional
Z-Image face stack is already gated. Above the floor the config passes no
"disk" value anywhere, which is what actually disables the behavior:
DiffSynth latches disk_offload once from offload_dtype, so pointing every
device at CUDA while leaving the sentinel would keep both the meta-drop and
the re-read.
The floor is set equal to the face floor rather than lower because that is
the configuration measured with both stacks resident; a tighter gate is
plausible but unvalidated. cpu_offload now forces both stacks to stream, so
a caller asking for low VRAM no longer gets the larger stack pinned anyway.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
