From owner-freebsd-current@FreeBSD.ORG  Fri Oct 28 22:23:41 2005
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To: "Steven Hartland" <killing@multiplay.co.uk>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Fri, 28 Oct 2005 22:36:19 BST."
	<005d01c5dc0c$7ad2c9c0$b3db87d4@multiplay.co.uk> 
Date: Sat, 29 Oct 2005 00:23:38 +0200
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Cc: Michael VInce <mv@roq.com>, John-Mark Gurney <gurney_j@resnet.uoregon.edu>,
	current@freebsd.org
Subject: Re: Timers and timing, was: MySQL Performance 6.0rc1 
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In message <005d01c5dc0c$7ad2c9c0$b3db87d4@multiplay.co.uk>, "Steven Hartland" 
writes:
>For interest I ran truss on a typical game server we run under
>FreeBSD to get a feel for how much this issue would affect
>their performance.
>Below is a small snippet from truss with -D which indicates
>that they would also benefit from work in this area.

Yes, by about a factor of 0.000005 seconds every .5 seconds
or a factor of 1/100000 :-)

>0.000010894 gettimeofday({1130534881 790912},0xbfbfe9f0) = 0 (0x0)

Grab timestamp

>0.009520674 nanosleep({0 5000000})               = 0 (0x0)

Sleep half a second

(rinse, repeat)


It would have been much more interesting if the server was doing
something...

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.