Reduce number of processes spawned for gloo_test.TestCase.test_forked_cw (#23221)
Summary:
It used to be run with comm_size=8, which causes flaky results in a
stress run. The flakiness was caused by too many listening sockets
being created by Gloo context initialization (8 processes times 7
sockets times 20-way concurrency, plus TIME_WAIT).
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23221
ghstack-source-id: 86995596
Reviewed By: d4l3k
Differential Revision: D16437834
fbshipit-source-id: 998d0e2b087c0ab15eca64e308059c35e1b51e7b
