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Re: [Xen-devel] schedulers and topology exposing questions



On Thu, Jan 28, 2016 at 09:55:45AM +0000, Dario Faggioli wrote:
> On Wed, 2016-01-27 at 15:53 +0000, George Dunlap wrote:
> > On 27/01/16 15:27, Konrad Rzeszutek Wilk wrote:
> > >Â
> > > So Elena started looking at the CPU bound and seeing how Xen
> > > behaves then
> > > and if we can improve the floating situation as she saw some
> > > abnormal
> > > behavious.
> >
> > OK -- if the focus was on the two cases where the Xen credit1
> > scheduler
> > (apparently) co-located two cpu-burning vcpus on sibling threads,
> > then
> > yeah, that's behavior we should probably try to get to the bottom of.
> >
> Well, let's see the trace.Â

Hey Dario

Please disregard the previous email with topology information.
It was incorrect and I am attaching the topology that is actually result
of Joao smt patches application.


Elena
>
> In any case, I'm up to trying hooking the SMT load balancer in
> runq_tickle (which would mean doing it upon every vcpus wakeup).
>
> My gut feeling is that the overhead my outwieght the benefit, and that
> it will actually reveal useful only in a minority of the
> cases/workloads, but it's maybe worth a try.

>
> Regards,
> Dario
> --
> <<This happens because I choose it to happen!>> (Raistlin Majere)
> -----------------------------------------------------------------
> Dario Faggioli, Ph.D, http://about.me/dario.faggioli
> Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK)
>


Attachment: cpuinfo
Description: Text document

Attachment: sched_domains
Description: Text document

Attachment: topology_smt_patches
Description: Text document

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