On Fri, 2016-10-07 at 22:55 +0000, Chopra, Manish wrote: > Hello Folks, > > I am experimenting aRFS with our NIC devices, and for that I have > kernel 4.8.x installed with below config. > > CONFIG_RPS=y > CONFIG_RFS_ACCEL=y > > # cat /proc/cpuinfo | grep processor > processor : 0 > processor : 1 > processor : 2 > processor : 3 > processor : 4 > processor : 5 > processor : 6 > processor : 7 > processor : 8 > processor : 9 > processor : 10 > processor : 11 > processor : 12 > processor : 13 > processor : 14 > processor : 15 > > I configured rps_sock_flow_entries and our NIC rx queues with below > values > > echo 32768 > /proc/sys/net/core/rps_sock_flow_entries > echo 4096 > /sys/class/net/p4p1/queues/rx-0/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-1/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-2/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-3/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-4/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-5/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-6/rps_flow_cnt > echo 4096 > /sys/class/net/p4p1/queues/rx-7/rps_flow_cnt > > echo ffff > /sys/class/net/p4p1/queues/rx-0/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-1/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-2/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-3/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-4/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-5/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-6/rps_cpus > echo ffff > /sys/class/net/p4p1/queues/rx-7/rps_cpus > > Below is IRQ affinity configuration for NIC irqs used. > > # cat /proc/irq/67/smp_affinity_list > 8 > # cat /proc/irq/68/smp_affinity_list > 9 > # cat /proc/irq/69/smp_affinity_list > 10 > # cat /proc/irq/70/smp_affinity_list > 11 > # cat /proc/irq/71/smp_affinity_list > 12 > # cat /proc/irq/72/smp_affinity_list > 13 > # cat /proc/irq/73/smp_affinity_list > 14 > # cat /proc/irq/74/smp_affinity_list > 15 > > Driver has required feature NETIF_F_NTUPLE set, ndo_rx_flow_steer() > registered and I am running UDP multiple connections stream using > netperf to the host where I am experimenting aRFS. > > # netperf -V > Netperf version 2.7.0 > > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 8,8 -- -m 1470 -P > 5001,48512 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 9,9 -- -m 1470 -P > 5001,37990 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 10,10 -- -m 1470 -P > 5001,40302 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 11,11 -- -m 1470 -P > 5001,39071 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 12,12 -- -m 1470 -P > 5001,58994 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 13,13 -- -m 1470 -P > 5001,59884 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 14,14 -- -m 1470 -P > 5001,40282 & > netperf -H 192.168.200.40 -t UDP_STREAM -l 150 -T 15,15 -- -m 1470 -P > 5001,56042 & > > I see that our registered callback for ndo_rx_flow_steer() "NEVER" > gets invoked for UDP packets, with TCP_STREAM I do see it gets > invoked. > But while running UDP_STREAM I see it gets invoked for some of TCP > packets as netperf also uses TCP managed connections while running > UDP_STREAM. > > My initial investigation suspects that while running UDP_STREAM with > netperf, rps_sock_flow_table doesn't get updated, as packets never > reach to the flow of inet_recvmsg() > where it gets updated using sock_rps_record_flow(). Which might be the > reason it never invokes NIC's flow steering handler ? > > Please note that when I run UDP stream using "iperf" - I do see that > our registered callback function for flow steering gets invoked for > "UDP" packets. > I am not sure if I am missing something in configuration or something > else which is I am unware of ? > > I appreciate any help for this.
Make sure you use connected UDP flows netperf -t UDP_STREAM ... -- -N -n Otherwise, one UDP socket can be involved in millions of 4-tuples (aka flows)
