pytorch

a197f3fe - [FSDP/Checkpoint] Activation offload support in checkpoint_wrapper (#70165)

[FSDP/Checkpoint] Activation offload support in checkpoint_wrapper (#70165) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/70165 Implements activation offload support in checkpoint_wrapper API via save_on_cpu hooks. We avoid modifying the torch.utils.checkpoint implementation and instead compose offload + checkpoint using the save_on_cpu hook for the former. ghstack-source-id: 146078900 Test Plan: CI Reviewed By: zhaojuanmao Differential Revision: D33228820 fbshipit-source-id: 98b4da0828462c41c381689ee07360ad014e808a