pytorch

43df03de - [Gradient Compression] Replace torch.sqrt(torch.sum(col ** 2)) by torch.norm() (#51629)

[Gradient Compression] Replace torch.sqrt(torch.sum(col ** 2)) by torch.norm() (#51629) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/51629 Leverage the existing util functions as much as possible for potential performance gain. Original PR issue: Investigate Applying PowerSGD to Communication Hook for Gradient Compression #47202 ghstack-source-id: 120919883 Test Plan: buck test mode/dev-nosan caffe2/test/distributed:c10d -- test_powerSGD_ddp_comm_hook_nccl No performance regression: f248664994 uses `torch.norm()` ``` total: 32 GPUs -- 32 GPUs: p25: 1.050 30/s (batch size 32) p50: 1.230 26/s (batch size 32) p75: 1.449 22/s (batch size 32) p90: 1.611 19/s (batch size 32) p95: 1.702 18/s (batch size 32) backward: 32 GPUs -- 32 GPUs: p25: 0.769 41/s (batch size 32) p50: 0.920 34/s (batch size 32) p75: 1.139 28/s (batch size 32) p90: 1.322 24/s (batch size 32) p95: 1.440 22/s (batch size 32) ``` f248678690 does not use `torch.norm()` ``` total: 32 GPUs -- 32 GPUs: p25: 1.056 30/s (batch size 32) p50: 1.249 25/s (batch size 32) p75: 1.443 22/s (batch size 32) p90: 1.608 19/s (batch size 32) p95: 1.711 18/s (batch size 32) backward: 32 GPUs -- 32 GPUs: p25: 0.777 41/s (batch size 32) p50: 0.939 34/s (batch size 32) p75: 1.127 28/s (batch size 32) p90: 1.322 24/s (batch size 32) p95: 1.448 22/s (batch size 32) ``` Reviewed By: pritamdamania87 Differential Revision: D26219835 fbshipit-source-id: 31d8ad3401d4efced4a6069f4f1e169ea3372697