[GH-ISSUE #33] Why doesn't it lead to a deadlock when only some threads call nvshmem_barrier_all？ #32

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opened 2026-10-26 09:52:52 +00:00 by bsakaguchi · 1 comment

bsakaguchi commented

2026-10-26 09:52:52 +00:00

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Originally created by @MoringKing on GitHub (Mar 1, 2025).
Original GitHub issue: https://github.com/deepseek-ai/DeepEP/issues/33

nvshmem_barrier_all is used to synchronize all PE globally, but this function is called only when thread_id is equal to 32. Will it cause deadlock?

Originally created by @MoringKing on GitHub (Mar 1, 2025). Original GitHub issue: https://github.com/deepseek-ai/DeepEP/issues/33 nvshmem_barrier_all is used to synchronize all PE globally, but this function is called only when thread_id is equal to 32. Will it cause deadlock? <img width="894" alt="Image" src="https://github.com/user-attachments/assets/4cf35430-da0e-400a-b006-9385890faa8d" />

bsakaguchi closed this issue

2026-10-26 09:52:52 +00:00

bsakaguchi commented

2026-10-26 09:52:53 +00:00

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@LyricZhao commented on GitHub (Mar 3, 2025):

No, nvshmem_barrier_all can be called with only one thread (there's also some API warp/block-level API like nvshmemx_barrier_all_block). For more details, please refer to https://docs.nvidia.com/nvshmem/api/index.html.

@LyricZhao commented on GitHub (Mar 3, 2025): No, `nvshmem_barrier_all` can be called with only one thread (there's also some API warp/block-level API like `nvshmemx_barrier_all_block`). For more details, please refer to https://docs.nvidia.com/nvshmem/api/index.html.

bsakaguchi referenced this issue

2026-10-26 09:53:39 +00:00

[GH-ISSUE #74] test_internode.py hangs at internode.cu:dispatch(...) #68

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2026-10-26 09:56:30 +00:00

[GH-ISSUE #270] A timeout error occurred when running test_internode.py on four devices. #200

bsakaguchi referenced this issue

2026-10-26 09:56:40 +00:00

[GH-ISSUE #290] Running the test case on a 2-node H20 3E machine failed with internode.cu:1029 'unspecified launch failure' #208

bsakaguchi referenced this issue

2026-10-26 10:00:38 +00:00

[PR #32] [MERGED] update path #427