This NCCL release includes the following key features and enhancements.

• Improve performance tuning on large number of ranks.
• Add NCCL_P2P_LEVEL and NCCL_IB_GDR_LEVEL knobs to finely control when to use GPU Direct P2P and GPU Direct RDMA.
• Reduce setup time for large scale jobs.
• Increased maximum number of rings supported to 16.
• Added a runtime NCCL version API: ncclGetVersion().
• Added NCCL_DEBUG_SUBSYS to allow filtering of NCCL_DEBUG=INFO logging from different subsystems.
• Support for Turing based systems.

• Fix hang on Power platforms.
• Fix low inter-node bandwidth issue on multi-DGX2 systems.
• Fix crash when used with PID isolator.