From owner-freebsd-hackers@FreeBSD.ORG  Thu May 31 13:00:23 2012
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Date: Thu, 31 May 2012 16:00:13 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: Ryan Stone <rysto32@gmail.com>
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Cc: freebsd-hackers@FreeBSD.org, Adrian Chadd <adrian@FreeBSD.org>,
	Alexander Motin <mav@FreeBSD.org>, John Baldwin <jhb@FreeBSD.org>
Subject: Re: ULE/sched issues on stable/9 - why isn't preemption occuring?
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on 31/05/2012 15:48 Ryan Stone said the following:
> On Thu, May 31, 2012 at 8:33 AM, Andriy Gapon <avg@freebsd.org> wrote:
>> In this vein it might make sense to enable KTR and KTR_SCHED in GENERIC.
> 
> KTR_SCHED comes with a performance hit.

Yep, I realize that.  But I hope that it is not too huge for typical users of
GENERIC.  BTW, by "enable" I actually meant to compile it in, not really activate it.

> Besides, with the DTrace
> sched provider that I committed this month (and MFC'ed yesterday) you
> can collect schedgraph data with a D script.

Thank you for the reminder.  I am still to try it out.

-- 
Andriy Gapon