From owner-freebsd-hackers@FreeBSD.ORG  Mon Jan 30 21:10:09 2012
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Date: Mon, 30 Jan 2012 16:10:07 -0500
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From: Ryan Stone <rysto32@gmail.com>
To: Attilio Rao <attilio@freebsd.org>
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Cc: Peter Holm <pho@freebsd.org>, Florian Smeets <flo@smeets.im>,
	freebsd-hackers@freebsd.org
Subject: Re: Kernel threads inherit CPU affinity from random sibling
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On Sat, Jan 28, 2012 at 8:22 AM, Attilio Rao <attilio@freebsd.org> wrote:
> Do you have a pathological test-case for it? Are you going to test the patch?
>
> Thanks,
> Attilio

I tested the patch last night.  Previously I was able to see a
softclock thread preempted for over 1ms on machine where 4/8 cores
were lightly loaded.  With this patch I can see that the softclock
threads are free to migrate cores and they no longer see long
scheduling latencies.