`load` took the host copies before checking which tensors were missing from
the device, so with `vae_cpu_offload=False` — where the loader builds the VAEs
on CUDA and `unload` is never called — it pulled about 11 GB per rank back over
PCIe once and kept a pinned mirror of it for the life of the process, for a
module that never leaves the device.
It now asks what is absent first and returns early when nothing is. The
offloaded path is unchanged: weights still round-trip and come back bit
identical.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
