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Sender: Alexander Motin <mavbsd@gmail.com>
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Date: Fri, 19 Nov 2010 19:45:41 +0200
From: Alexander Motin <mav@FreeBSD.org>
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To: Andriy Gapon <avg@freebsd.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: statclock(n)
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Hi.

Andriy Gapon wrote:
> I wonder if instead of calling statclock() multiple times (after an idle period)
> we couldn't call it just with an appropriate N parameter.
> So some stats like e.g. cp_time[] could do +=N instead of ++.
> Other stats ru_ixrss need to be updated only once.
> Similarly, N could be passed further down to sched_clock() and handled there too.

I think yes. It is reasonable. Initially hardclock() was also called in
a loop. It was just rewritten first because it is called more often
(more times), goes to hardware to sync time, and any way required
changes to work properly.

-- 
Alexander Motin