Add a selectable attention kernel via the diffusers set_attention_backend dispatcher. Attention is memory-bandwidth bound, so a better kernel is an end-to-end win orthogonal to the linear-weight quantisation (it speeds the QK/PV matmuls torchao never touches) and composes with torch.compile. auto picks the best exact backend for the device: cuDNN fused attention (_native_cudnn) on NVIDIA when a speed profile is active, measured ~1.18x end-to-end on a B200 (Z-Image 1024px/8 steps) with LPIPS ~0.004 vs the default (below the compile/quant noise floor); native SDPA elsewhere and when speed=off (so off stays bit-identical). Explicit native/cudnn/flash/flash3/flash4/sage/ xformers/aiter are honored, and an unavailable kernel falls back to the default rather than failing the load. New core/inference/diffusion_attention.py (normalize + per-device select + apply, best-effort, lazy imports). Set on pipe.transformer BEFORE compile in load_pipeline; attention_backend threads through begin_load / load_pipeline / status like the other load knobs. New request field attention_backend + status field. Hermetic CPU tests for normalize / select policy / apply fallback, plus route threading + 422. Measured via scripts/perf_levers_probe.py. |
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| .. | ||
| assets | ||
| auth | ||
| core | ||
| hub | ||
| loggers | ||
| models | ||
| plugins | ||
| requirements | ||
| routes | ||
| state | ||
| storage | ||
| tests | ||
| utils | ||
| __init__.py | ||
| _platform_compat.py | ||
| cloudflare_tunnel.py | ||
| colab.py | ||
| main.py | ||
| run.py | ||
| startup_banner.py | ||