See the comment [here](https://github.com/pytorch/pytorch/issues/132014#issuecomment-2379547400) (cc @H-Huang @awgu @kwen2501 @wanchaol @fegin @fduwjj @wz337 @wconstab @d4l3k @c-p-i-o @voznesenskym @penguinwu @EikanWang @jgong5 @Guobing-Chen @XiaobingSuper @zhuhaozhe @blzheng @wenzhe-nrv @jiayisunx @ipiszy @yf225 @chenyang78 @kadeng @muchulee8 @ColinPeppler @amjames @desertfire @chauhang @aakhundov @XilunWu @rec) - this PR updates `_unsafe_set_version_counter` to accept a list of tensors, for overhead-sensitive users (e.g. distributed) who need to hide VC bumps from autograd on a large list of tensors without wanting to suffer the overhead of going from python->C++ separately for every tensor in the list.
I left the binding in pybind, and used a `std::vector`. if we **really** need to optimize overhead even further, we could write a manual cpython binding.
I use this updated API in the next PR to fix FSDP2, so that it properly hides the VC of all `all_gather_buffer` tensors in its call to `split_with_sizes_copy.out(all_gather_buffers)`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/137921
Approved by: https://github.com/awgu, https://github.com/albanD
We override the `__call__` method and register fake, functional, proxy default dispatch mode implementation in its python_key_mode_table.
The idea is:
1. when inputs contains FakeScriptObject, we dispatch it through _get_dispatch mechanism. We implement dispatch mode keys automatically in the operator's constructor.
2. when inputs are not fakified, we dispatch through the original c++ dispatcher.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/123367
Approved by: https://github.com/zou3519
