pytorch

07104ca9 - [c10d] Make it default that PG do not perform barrier after init (#103033)

[c10d] Make it default that PG do not perform barrier after init (#103033) Both internal and OSS users trying https://github.com/pytorch/pytorch/pull/99937 report that their workloads perform normally even with the barrier removed and see a scalability win. Thus in this PR, we decide to make it default that PG do not perform a barrier after init. In the discussion of #99937, people point out that such barrier might be needed for c10d + RPC cases. IMO, this need originates from RPC's programming model and should be RPC or RPC user's responsibility to deal with. That is, with other functions/libraries, it can happen too. So the need for c10d to do so big a favor is not justified IMO. Also good to remove it before users become reliant on this barrier. Pull Request resolved: https://github.com/pytorch/pytorch/pull/103033 Approved by: https://github.com/XilunWu