Auto-detect NCCL network configuration - SLURM #565
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- Add get_nccl_env_vars() function to automatically detect network configuration - Detects InfiniBand interfaces (ibp*, ib*) and enables them automatically - Falls back to Ethernet (^lo) if no InfiniBand is available - Respects user-set NCCL environment variables - Sets NCCL_SOCKET_IFNAME and NCCL_IB_DISABLE based on actual cluster hardware - Eliminates need for manual NCCL configuration
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allenwang28
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thanks @HosseinKaviani-H!
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allenwang28
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)" This reverts commit f99d7aa.
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Auto-detect NCCL network configuration
Automatically detects and configures NCCL network settings based on actual cluster hardware instead of requiring manual configuration.
Changes:
NCCL_SOCKET_IFNAMEandNCCL_IB_DISABLEif already configuredExample:
NCCL_SOCKET_IFNAME=ibp230s0,ibp212s0,...andNCCL_IB_DISABLE=0NCCL_SOCKET_IFNAME=^loandNCCL_IB_DISABLE=1