all my mlx cx5 2*100G cards unable to line rate speed

Hi all,

I have two mellanox cx5 2*100G nic. I following the dpdk 20.11 mlx performance report Test#3 Mellanox ConnectX-5 Ex 100GbE Throughput at Zero Packet

Loss (1x 100GbE)。

mlx_topoSpirent TestCenter send 300B packet 39Mpps,server run dpdk testpmd in fwd io mode,but throughput just 85% of line ratre. How to check what problem cause the low perfmance ?

More infomation please see the attachement file.

Mellanox CX5 unable to line rate speed.docx (484 KB)

Hello Eason,

Thank you for posting your inquiry on the NVIDIA Networking Community.

Based on the information provided, performance difference can occur, when not the same test setup is being used for these performance tests. Also from your documentation, it is clear that you are using a ConnectX-5 EN adapter and not the ConnectX-5 Ex adapter (which is a low-latency version of the ConnectX-5 and is PCIe Gen4 X16, see PB →

Also we recommend to follow the performance reports from the latest DPDK version available.

Thank you and regards,

~NVIDIA Networking Technical Support