On 31.08.2016 22:42, Eric Dumazet wrote: > On Wed, 2016-08-31 at 21:40 +0200, Jesper Dangaard Brouer wrote: > >> I can confirm the improvement of approx 900Kpps (no wonder people have >> been complaining about DoS against UDP/DNS servers). >> >> BUT during my extensive testing, of this patch, I also think that we >> have not gotten to the bottom of this. I was expecting to see a higher >> (collective) PPS number as I add more UDP servers, but I don't. >> >> Running many UDP netperf's with command: >> super_netperf 4 -H 198.18.50.3 -l 120 -t UDP_STREAM -T 0,0 -- -m 1472 -n -N > > Are you sure sender can send fast enough ? > >> >> With 'top' I can see ksoftirq are still getting a higher %CPU time: >> >> PID %CPU TIME+ COMMAND >> 3 36.5 2:28.98 ksoftirqd/0 >> 10724 9.6 0:01.05 netserver >> 10722 9.3 0:01.05 netserver >> 10723 9.3 0:01.05 netserver >> 10725 9.3 0:01.05 netserver > > Looks much better on my machine, with "udprcv -n 4" (using 4 threads, > and 4 sockets using SO_REUSEPORT)
Would it make sense to include used socket backlog in udp socket lookup compute_score calculation? Just want to throw out the idea, I actually could imagine to also cause bad side effects.
