On Sat, 10 Nov 2018 22:53:53 +0100 Paweł Staszewski <pstaszew...@itcare.pl> wrote:
> Now im messing with ring configuration for connectx5 nics. > And after reading that paper: > https://netdevconf.org/2.1/slides/apr6/network-performance/04-amir-RX_and_TX_bulking_v2.pdf > Do notice that some of the ideas in that slide deck, was never implemented. But they are still on my todo list ;-). Notice how that it show that TX bulking is very important, but based on your ethtool_stats.pl, I can see that not much TX bulking is happening in your case. This is indicated via the xmit_more counters. Ethtool(enp175s0) stat: 2630 ( 2,630) <= tx_xmit_more /sec Ethtool(enp175s0) stat: 4956995 ( 4,956,995) <= tx_packets /sec And the per queue levels are also avail: Ethtool(enp175s0) stat: 184845 ( 184,845) <= tx7_packets /sec Ethtool(enp175s0) stat: 78 ( 78) <= tx7_xmit_more /sec This means that you are doing too many doorbell's to the NIC hardware at TX time, which I worry could be what cause the NIC and PCIe hardware not to operate at optimal speeds. -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer