mirror of
https://github.com/huggingface/lerobot.git
synced 2026-05-27 22:49:48 +00:00
pepijn
4913356564
Replaces the per-layer ``modeling_gemma.eager_attention_forward`` call with ``torch.nn.functional.scaled_dot_product_attention`` in ``compute_layer_complete`` (pi05) and ``_compute_layer_ki`` (pi052). PyTorch SDPA picks the memory-efficient kernel for the block-bidirectional 4D additive mask the dual-expert model uses (FA2 / FA3 reject it because they only accept causal / sliding-window / varlen patterns). The shared ``sdpa_attention_forward`` helper mirrors the eager signature so the call sites are unchanged. Selective AC: removes the redundant outer ``_apply_checkpoint(forward_func, ...)`` wrap in ``PI05Pytorch.forward``. Per-layer checkpointing inside ``PaliGemmaWithExpertModel.forward`` already handles activation recompute; the outer wrap was double-recomputing the whole backbone. +14% steps/sec on its own (job 22161405 vs 22161398, 1xH100). groot: drop ``@strict`` on ``GR00TN15Config`` — newer ``huggingface_hub`` rejects ``@strict`` on non-dataclass ``PretrainedConfig`` subclasses, which was blocking imports of any sibling policy through ``lerobot.policies.factory``. New ``examples/benchmark/bench_pi052_step.py`` (+ slurm sweeps v1..v8) times PI052Policy.forward+backward (optionally with AdamW) on synthetic inputs. Headline numbers on 1xH100 with KI=True, GC=True, L=512, 4.14 B trainable params, AdamW state in bf16: pre-SDPA eager BS=8 610ms 19.5 GiB -> 13.1 samples/s sdpa BS=8 + compile=default 413ms 19.5 GiB -> 19.3 samples/s sdpa BS=16 + compile=default 715ms 37.3 GiB -> 22.4 samples/s sdpa BS=32 + compile=default 1325ms 44.8 GiB -> 24.2 samples/s sdpa BS=40 + compile=default 1665ms 48.6 GiB -> 24.0 samples/s Parity tests in ``tests/policies/pi052/test_pi052_sdpa_attention.py`` cover fp32 / bf16 / GQA / MHA forward + backward — output and grads match the eager path within bf16 tolerance. Also ships ``examples/benchmark/fsdp_pi052.yaml`` (FSDP2 accelerate config wrapping GemmaDecoderLayer + SiglipEncoderLayer) for the follow-up multi-GPU memory sharding work. Co-authored-by: Cursor <cursoragent@cursor.com>