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

From: Peter Zijlstra
Date: Sun Oct 25 2009 - 04:01:45 EST


On Sat, 2009-10-24 at 13:07 -0700, Arjan van de Ven wrote:
> Subject: sched: Disable affine wakeups by default
> From: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
>
> The global affine wakeup scheduler feature sounds nice, but there is a problem
> with this: This is ALSO a per scheduler domain feature already.
> By having the global scheduler feature enabled by default, the scheduler domains
> no longer have the option to opt out.
>
> There are domains (for example the HT/SMT domain) that have good reason to want
> to opt out of this feature.
>
> With this patch they can opt out, while all other domains currently default to
> the affine setting anyway.
>
> Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
>

Hell no, that'll destroy many workloads. What you could possibly do is
disable it for sched domains that are known to share cache, maybe.

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