Re: [patch] CFS scheduler, v3

From: William Lee Irwin III
Date: Fri Apr 20 2007 - 16:03:32 EST


On Fri, 20 Apr 2007, William Lee Irwin III wrote:
>> I'm not really convinced it's all that worthwhile of an optimization,
>> essentially for the same reasons as you, but presumably there's a
>> benchmark result somewhere that says it matters. I've just not seen it.

On Fri, Apr 20, 2007 at 12:44:55PM -0700, Christoph Lameter wrote:
> If it is true that we frequently remotely write the per cpu runqueue
> data then we may have a NUMA scalability issue.

>From the discussion on Suresh's thread, it appears to have sped up a
database benchmark 0.5%.

Last I checked it was workload-dependent, but there were things that
hammer it. I mostly know of the remote wakeup issue, but there could
be other things besides wakeups that do it, too.


-- wli
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