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Date: Thu, 27 Oct 2005 16:29:23 +0800
From: David Xu <davidxu@freebsd.org>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: current@freebsd.org, Marian Hettwer <MH@kernel32.de>
Subject: Re: MySQL Performance 6.0rc1
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Poul-Henning Kamp wrote:
> In message <43607DD5.3020708@freebsd.org>, David Xu writes:
> 
> 
>>Check gettimeofday syscall, it follows every I/O syscall, I think
>>our gettimeofday is tooooooo expensive, if we can directly get time from
>>memory, the performance will be improved further.
> 
> 
> Why would anybody take a timestamp at all I/O syscalls ? 
> 
> "I wonder why my car can only go 30 km/h with the trunk full of concrete" ?
> 
> In a data base application I could possibly understand a timestamp
> after every write.
> 
> But after _all_ I/O syscalls ?  That's just plain stupid...
> 

Don't panic, I agree that is stupid code, but I can not change it, it
is not written by me, sorry!