#!/usr/bin/env bash # NCCL optimization script for distributed training # Usage: source scripts/optimize_nccl.sh # NCCL timeout and communication settings export NCCL_TIMEOUT=3600 # 1 hour timeout (default 30min) export NCCL_ASYNC_ERROR_HANDLING=1 # Enable async error handling export NCCL_MAX_NCHANNELS=4 # Reduce number of channels for better stability export NCCL_MIN_NCHANNELS=4 # Set minimum channels export NCCL_BUFFSIZE=4194304 # 4MB buffer size # Socket communication optimization export NCCL_SOCKET_IFNAME=eth0 # Use specific network interface export NCCL_IB_DISABLE=1 # Disable InfiniBand if not available # GPU memory and communication optimization export CUDA_LAUNCH_BLOCKING=0 # Non-blocking CUDA operations export NCCL_P2P_DISABLE=0 # Enable peer-to-peer communication export NCCL_SHM_DISABLE=0 # Enable shared memory # Debugging (set to 0 for production) export NCCL_DEBUG=INFO # INFO level debugging export TORCH_DISTRIBUTED_DEBUG=DETAIL # Detailed distributed debugging echo "NCCL optimization settings applied:" echo "- NCCL_TIMEOUT: $NCCL_TIMEOUT" echo "- NCCL_ASYNC_ERROR_HANDLING: $NCCL_ASYNC_ERROR_HANDLING" echo "- NCCL_MAX_NCHANNELS: $NCCL_MAX_NCHANNELS" echo "- NCCL_DEBUG: $NCCL_DEBUG" echo "" echo "To use these settings, run:" echo " source scripts/optimize_nccl.sh" echo " bash scripts/run_all_ablations.sh --group A"