On Sun, 2016-06-12 at 09:40 -0700, Dave Taht wrote: > Eric: > > Quick side question (from trying to understand the qdisc locking fixes > you recently landed in net-next) > > In the sqm-scripts, we are usually in a position where we are doing > both inbound and outbound rate limiting (htb + fq_codel or cake). We > typically run out of cpu or have mis-behavior on the inbound side, and > the cpu bottleneck appears to be in ksoftirqd. > > A) In my failing to make sense of all the dialog around these patches > ( https://lwn.net/Articles/687617/ ), it sounds like this (inbound > and outbound) processing are still locked to a single thread, > essentially?
Om a router, these discussions should not matter really, since the workload is about receiving/sending packets without user space intervention (well... I do hope this !) > > B) But you have eliminated lot of overhead in basic qdisc processing > to much cpu benefit and we should consider backporting these changes > to lede/openwrt (4.4)? It is possible that my recent patches avoiding the throttled bit manipulation might help. I measured between 7% and 8% change in my tests on x86 with HTB qdisc. e69f73bfecb0178ae6bd20eb778211739cd71fab Merge branch 'remove-qdisc-throttle' 45f50bed1d808794e514e9eed0e579a8756ce2ba net_sched: remove generic throttled management 42117927cab5a13192ecc227bea19da5059ffc6c net_sched: netem: remove qdisc_is_throttled() use cca605dd4b3b2bfa381250b7dbbe16b124916f24 net_sched: cbq: remove a flaky use of qdisc_is_throttled() 8fe6a79fb8088a759b3dc57eb641fc3183ad72b8 net_sched: sch_plug: use a private throttled status _______________________________________________ Cake mailing list Cake@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/cake