Re: [LKP] Re: [sched] bdfcae1140: will-it-scale.per_thread_ops -37.0% regression

[Mathieu Desnoyers]

----- On Oct 21, 2020, at 9:54 PM, Xing Zhengjun zhengjun.xing@xxxxxxxxxxxxxxx wrote:
[...]
> In fact, 0-day just copy the will-it-scale benchmark from the GitHub, if
> you think the will-it-scale benchmark has some issues, you can
> contribute your idea and help to improve it, later we will update the
> will-it-scale benchmark to the new version.

This is why I CC'd the maintainer of the will-it-scale github project, Anton Blanchard.
My main intent is to report this issue to him, but I have not heard back from him yet.
Is this project maintained ? Let me try to add his ozlabs.org address in CC.

> For this test case, if we bind the workload to a specific CPU, then it
> will hide the scheduler balance issue. In the real world, we seldom bind
> the CPU...

When you say that you bind the workload to a specific CPU, is that done
outside of the will-it-scale testsuite, thus limiting the entire testsuite
to a single CPU, or you expect that internally the will-it-scale context-switch1
test gets affined to a single specific CPU/core/hardware thread through use of
hwloc ?

Thanks,

Mathieu

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com