RoCE · RDMA over Converged Ethernet
RDMA over Ethernet. ECN signals congestion; it does not make the fabric lossless. The design must state queueing and congestion control plus any PFC, retransmission/recovery, routing, buffering, and failure-handling choices.
Also written as: RoCEv2 · RoCEv1
Current numbers
51.2 TbpsBroadcom Jericho4 deep-buffer router; 3nm; HBM packet memory (~160× on-chip); RoCE over >100 km via 3.2 Tbps HyperPorts
tens of µsNVMe-oF read latency over RDMA (RoCE/IB) vs milliseconds for legacy NFS/iSCSI
~95%Spectrum-X / tuned-RoCE effective throughput vs raw link rate under collective load; untuned RoCE can collapse to ~60%