Messages in this thread | | | Subject | Re: [PATCH 3/3] sched: Disable affine wakeups by default | From | Mike Galbraith <> | Date | Mon, 26 Oct 2009 06:47:58 +0100 |
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On Sun, 2009-10-25 at 22:36 -0700, Arjan van de Ven wrote: > On Mon, 26 Oct 2009 06:08:54 +0100 > Mike Galbraith <efault@gmx.de> wrote:
> > > > > > or we just use SD_WAKE_AFFINE / SD_BALANCE_WAKE for this... > > > > I don't see how. Oh, you mean another domain level, top level being > > cache property, and turn off when degenerating? That looks like it'd > > be a problem, but adding SD_CACHE_SIBLING or whatnot should work. > > Problem is how to gain knowledge of whether multicores share a cache > > or not. > > Actually I meant setting the SD_BALANCE_WAKE flag for the SMT and MC > domains (and then making sure that "MC" really means "shares LLC" in > the arch code), and then using this as indication in the sched code..
I don't think we can do that, because SD_WAKE_BALANCE already has a different meaning. SD_WAKE_AFFINE could be used though, affine wakeups have always been a cache thing, and for trying to keep things affine to a package or whatnot, we have SD_PREFER_LOCAL. Sounds clean to me.
> 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.
-Mike
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