Introduction to AWS Interconnect Technologies from a Distributed Training Perspective - GPU-to-GPU Communication Using NCCL in AWS Environments | Amazon Web Services

AWS published a technical guide on using NCCL over EFA to speed up GPU-to-GPU communication in distributed training.

The post contrasts NCCL-based collective communication with traditional MPI-style CPU communication and explains why the GPU path matters.

It also outlines the AWS software stack and configuration needed for EFA to work properly, including libfabric and aws-ofi-nccl.

The article highlights how tuning AWS networking can reduce latency and improve throughput for large-scale training workloads.