InfiniBand vs RoCEv2: Choosing the Right Network for Large-Scale AI

In large-scale AI environments, overall performance is limited by the network communication speed between GPUs. Technologies like RDMA and GPUDirect were developed to bypass CPU bottlenecks and allow GPUs to communicate directly. The two primary networking technologies enabling this are InfiniBand and RoCEv2. InfiniBand is a specialized, high-performance fabric that provides ultra-low latency and avoids packet loss but is expensive and requires proprietary hardware. RoCEv2 brings RDMA capabilities to standard Ethernet networks, offering a more cost-effective and flexible alternative that relies on careful network tuning to achieve comparable performance.