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Message-ID: <3C859909.30602@candelatech.com>
Date: Tue, 05 Mar 2002 21:20:25 -0700
From: Ben Greear <greearb@candelatech.com>
Organization: Candela Technologies
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To: Davide Libenzi <davidel@xmailserver.org>
CC: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: a faster way to gettimeofday?
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Davide Libenzi wrote:

> On Tue, 5 Mar 2002, Ben Greear wrote:
> 
> 
>>I have a program that I very often need to calculate the current
>>time, with milisecond accuracy.  I've been using gettimeofday(),
>>but gprof shows it's taking a significant (10% or so) amount of
>>time.  Is there a faster (and perhaps less portable?) way to get
>>the time information on x86?  My program runs as root, so should
>>have any permissions it needs to use some backdoor hack if that
>>helps!
>>
> 
> If you're on x86 you can use collect rdtsc samples and convert them to ms.
> You'll get even more then ms accuracy.


Can I do this from user space?  If so, any examples or docs
you can point me to?

Also, I'm looking primarily for a speed increase, not an accuracy
increase.

Thanks for the response!

Ben


> 
> 
> 
> 
> - Davide
> 
> 
> 
> -
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-- 
Ben Greear <greearb@candelatech.com>       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear


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