Users Guide

Table Of Contents
Broadcom NetXtreme-E-UG304-2CS
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NetXtreme-E User Guide User Guide for Dell Platforms
a. Server Side: ib_send_bw -d <RoCE Node> --report_gbits
b. Client Side: ib_send_bw -d <RoCE Node> --report_gbits <Server IP>
NOTE: With dual-port NICs, if both ports are on the same subnet, RDMA perftest commands may fail. The is caused by
an arp flux issue in Linux. Use multiple subnets for testing or bringing the other interface down.
14.2.5 RoCE Congestion Control
Broadcom NetXtreme Congestion Control (NCC) is a standards-based congestion control mechanism for RDMA over
Ethernet v2 (RoCEv2), which utilizes Explicit Congestion Notification (RFC 3168) to signal to RoCE transmitting stations the
congestion status of the network, which is used by NetXtreme-E network interface cards (NICs) to control transmit rate,
thereby reducing congestion, reducing packet drops, and minimizing network latency by keeping switch transmit queues
minimally loaded.
NCC can work in conjunction with Flow Control including pause frames and Priority Flow Control to guarantee a lossless
network, or NCC can operate alone.