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Date: Fri, 28 Oct 2005 18:14:52 +0800
From: David Xu <davidxu@freebsd.org>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: Pertti Kosunen <pertti.kosunen@pp.nic.fi>, current@freebsd.org,
	"Yuriy N. Shkandybin" <jura@networks.ru>
Subject: Re: Timers and timing, was: MySQL Performance 6.0rc1
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Poul-Henning Kamp wrote:
> In message <4361F057.4030904@pp.nic.fi>, Pertti Kosunen writes:
> 
> 
>>Does polling affect to this test?
> 
> 
> Not apart from the CPU overhead.
> 
> 	sysctl kern.timecounter.hardware
> 
> is much more important.
> 
> and all the reports here which fail to include it are mostly
> useless.
> 
> 
I suspect because our time() function in libc uses gettimeofday,
this further causes lots of gettimeofday syscall.