Re: [PATCH net-next 0/4] net: rps/rfs improvements

[Jakub Kicinski <kuba@kernel.org>]

On Thu, 30 Mar 2023 05:39:35 +0200 Eric Dumazet wrote:
> > This was from "grep NET_RX /proc/softirqs" (more exactly a tool
> > parsing /proc/softirqs)
> >
> > So it should match the number of calls to net_rx_action(), but I can
> > double check if you want.
> >
> > (I had a simple hack to enable/disable the optimizations with a hijacked sysctl)  
> 
> Trace of real debug session, because numbers ;)
> Old platform with two Intel(R) Xeon(R) Gold 6268L CPU @ 2.80GHz  (96
> threads total)
> 
> 600 tcp_rr flows
> 
> iroa23:/home/edumazet# cat /proc/sys/net/core/netdev_max_backlog
> 1000
> iroa23:/home/edumazet# ./interrupts
> hrtimer:99518 cal:2421783 timer:1034 sched:80505 rcu:7661 rps:2390765
> net_tx:43 net_rx:3344637 eth1-rx:295134 eth1-tx:558933 eth1:854074
> ^C
> iroa23:/home/edumazet# echo 1001 >/proc/sys/net/core/netdev_max_backlog
> iroa23:/home/edumazet# ./interrupts
> hrtimer:99545 cal:2358993 timer:1086 sched:77806 rcu:10928 rps:2419052
> net_tx:21 net_rx:3016301 eth1-rx:294612 eth1-tx:560331 eth1:855083
> ^C
> 
> echo "(3344637 - 3016301)/3344637" | bc -ql
> .09816790282473105452

Very nice, thanks! (I didn't know about /proc/softirqs !)