benchmark

82cd8520 - Use proper grad mode during model validation to avoid OOM (#168176)

Use proper grad mode during model validation to avoid OOM (#168176) Summary: Flux image generation pipeline takes about 32G. Our benchmark suite often does a deepcopy, which adds another 32G. And if we run with `requires_grad=True` (the default for HF models), we'll OOM on a A100 80G. Note that we already use `pick_grad` in most other places, so this patch simply improves that coverage. X-link: https://github.com/pytorch/pytorch/pull/168176 Approved by: https://github.com/Lucaskabela Reviewed By: georgehong Differential Revision: D98008600 fbshipit-source-id: e47804cf591f839877a0086bc4f9d8dcf6c2d044