[SymmMem] Increase minimum nthreads to cover sync needs in NVL72 #161983
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🔗 Helpful Links🧪 See artifacts and rendered test results at hud.pytorch.org/pr/161983
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| at::ceil_div(numel_per_split, numel_per_thread), | ||
| static_cast<size_t>(at::cuda::warp_size())); | ||
| num_threads = at::ceil_div(numel_per_split, numel_per_thread); | ||
| num_threads = max(num_threads, MAX_CUDA_P2P_DOMAIN_SIZE); |
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Better to pass world_size here and make max equal to world size
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…1984) Added a helper API to tell if the world is entirely within a P2P domain or crosses network. This is mainly for nblocks tuning purpose. (In later PRs) Pull Request resolved: #161984 Approved by: https://github.com/ngimel ghstack dependencies: #161983
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…orch#161983) `sync_remote_blocks` maps threads to peers. Previously min nthreads is warp size, which is too small to cover NVL72. Bumping it. Pull Request resolved: pytorch#161983 Approved by: https://github.com/ngimel
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…orch#161984) Added a helper API to tell if the world is entirely within a P2P domain or crosses network. This is mainly for nblocks tuning purpose. (In later PRs) Pull Request resolved: pytorch#161984 Approved by: https://github.com/ngimel ghstack dependencies: pytorch#161983
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…orch#161983) `sync_remote_blocks` maps threads to peers. Previously min nthreads is warp size, which is too small to cover NVL72. Bumping it. Pull Request resolved: pytorch#161983 Approved by: https://github.com/ngimel
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…orch#161984) Added a helper API to tell if the world is entirely within a P2P domain or crosses network. This is mainly for nblocks tuning purpose. (In later PRs) Pull Request resolved: pytorch#161984 Approved by: https://github.com/ngimel ghstack dependencies: pytorch#161983
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…orch#161984) Added a helper API to tell if the world is entirely within a P2P domain or crosses network. This is mainly for nblocks tuning purpose. (In later PRs) Pull Request resolved: pytorch#161984 Approved by: https://github.com/ngimel ghstack dependencies: pytorch#161983
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…orch#161984) Added a helper API to tell if the world is entirely within a P2P domain or crosses network. This is mainly for nblocks tuning purpose. (In later PRs) Pull Request resolved: pytorch#161984 Approved by: https://github.com/ngimel ghstack dependencies: pytorch#161983
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Stack from ghstack (oldest at bottom):
sync_remote_blocksmaps threads to peers. Previously min nthreads is warp size, which is too small to cover NVL72. Bumping it.cc @H-Huang @awgu @wanchaol @fegin @fduwjj @wz337 @wconstab @d4l3k @pragupta