AWS ParallelCluster
AWS ParallelCluster User Guide

Elastic Fabric Adapter

Elastic Fabric Adapter (EFA) is a network device that has OS-bypass capabilities for low-latency network communications with other instances on the same subnet. EFA is exposed by using libfabric, and can be used by applications using the Messaging Passing Interface (MPI). To use EFA with AWS ParallelCluster, add the line enable_efa = compute to the [cluster] section. EFA is supported by specific instance types (compute_instance_type is c5n.18xlarge, c5n.metal, i3en.24xlarge, or p3dn.24xlarge) on specific operating systems (base_os is alinux, centos7, ubuntu1604, or ubuntu1804). For more information about the enable_efa setting, see enable_efa. A cluster placement group should be used to minimize latencies between instances. See placement and placement_group.

For more information, see Elastic Fabric Adapter in the Amazon EC2 User Guide for Linux Instances and Scale HPC Workloads with Elastic Fabric Adapter and AWS ParallelCluster in the AWS Open Source Blog.