Re: [PATCH v2 1/2] sched/fair: Fix how load gets propagated from cfs_rq to its sched_entity

From: Dietmar Eggemann
Date: Thu May 04 2017 - 05:50:06 EST

On 04/05/17 07:21, Peter Zijlstra wrote:
> On Thu, May 04, 2017 at 07:51:29AM +0200, Peter Zijlstra wrote:
>> Urgh, and my numbers were so pretty :/
> Just to clarify on how to run schbench, I limited to a single socket (as
> that is what you have) and set -t to the number of cores in the socket
> (not the number of threads).
> Furthermore, my machine is _idle_, if I don't do anything, it doesn't do
> _anything_.

I can't recreate this problem running 'numactl -N 0 ./schbench -m 2 -t
10 -s 10000 -c 15000 -r 30' on my E5-2690 v2 (IVB-EP, 2 sockets, 10
cores / socket, 2 threads / core)

I tried tip/sched/core comparing running in 'cpu:/' and 'cpu:/foo' and

using your patch on top with all the combinations of {NO_}FUDGE,
{NO_}FUDGE2 with prop_type=shares_avg or prop_type_runnable.

Where you able to see the issue on tip/sched/core w/o your patch on your

The workload of n 60% periodic tasks on n logical cpus always creates a
very stable task distribution for me.