Fix Hang in tests#4575
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wdykas wants to merge 2 commits intoNVIDIA:mainfrom
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/ok to test 153003a |
kvareddy
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May 1, 2026
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@wdykas , is the PR ready? Still marked as draft. |
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I will take it out of draft when I have merged in main which I am trying now |
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/ok to test 6b6510f |
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just marked it as not draft |
ericharper
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May 1, 2026
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/ok to test 6b6510f |
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| # (some ranks capture cuda graphs while others run eager — the EP collective | ||
| # inside the graph never gets its peer). One rank in the edge state against a | ||
| # fixed peer is sufficient and is covered by the dedicated NCCL tests below. | ||
| _STATE_COMBOS = list(itertools.combinations_with_replacement(ALL_STATES, _EP_SIZE)) |
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if this fixes things, can we add the non cuda graphable states to ALL_STATES now?
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What does this PR do ?
destroy_model_parallel now destroys each NCCL subgroup tracked in _global_process_group_list (skipping the default at index 0) before nulling the python references. Without this, ProcessGroupNCCL objects and their NVLS multicast memory bindings accumulated across re-init cycles, eventually exhausting the NVLS pool and surfacing as a misleading transport/nvls.cc out of memory error.
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