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Date: Fri, 28 Oct 2005 18:43:10 +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 <4361FDBE.7000500@freebsd.org>, David Xu writes:
> 
> 
> the correct way to optimize this would be to add a time(2) systemcall
> which returns the value of the kernel global time_second.
> 

Can we make a page in kernel address space which is readable my user
code? put the variable in the page, I know read an integer is atomic-op,
needn't lock, so syscall is not needed.