Re: [PATCH 3/3] sched: Disable affine wakeups by default

Arjan van de Ven
2009-10-26T07:04:10Z

On Mon, 26 Oct 2009 08:01:12 +0100
Ingo Molnar <mingo@elte.hu> wrote:

>
> * Mike Galbraith <efault@gmx.de> wrote:
>
> > On Mon, 2009-10-26 at 06:47 +0100, Mike Galbraith wrote:
> > > On Sun, 2009-10-25 at 22:36 -0700, Arjan van de Ven wrote:
> >
> > > > if you're a multicore domain you better have a shared cache..
> > > > that's what it should mean. If it does not we should fix that.
> > >
> > > Sounds reasonable to me. I'll go make explosions.
> >
> > (Actually, if multicode and sibling does indeed mean shared cache,
> > no arch tinkering should be necessary, just reset SD_WAKE_AFFINE
> > when degenerating should work fine. Only thing is multicore with
> > siblings.. and test test test)
>
> Correct. There's a few cpus where multicore means separate caches but
> all modern CPUs have shared caches for cores so we want to tune for
> that.

for those cpus where mc means separate caches we should fix the arch
code to set up separate MC domains to be honest..
I can look into that in a bit..

--
Arjan van de Ven Intel Open Source Technology Centre
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