Re: [PATCH 2/2] sched/fair: Always propagate runnable_load_avg

From: Tejun Heo
Date: Thu May 04 2017 - 13:43:54 EST


Hello,

On Thu, May 04, 2017 at 10:19:46AM +0200, Vincent Guittot wrote:
> > schbench inside a cgroup and have some base load, it is actually
> > expected to show worse latency. You need to give higher weight to the
> > cgroup matching the number of active threads (to be accruate, scaled
> > by duty cycle but shouldn't matter too much in practice).
>
> I don't have to change anything cgroup weight with mainline to get
> good number which means that the base load which is quite close to
> null, is probably not the problem

So, while that *could* be the case, it could also be the baseline
incorrectly favoring the nested cfs_rqs over other tasks because of
the nested runnables being inflated with blocked load avgs. I think
it'd be a good idea to test with matching weight to put things on the
even ground.

Thanks.

--
tejun