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From: Parav Pandit <paravpandit@yahoo.com>
To: Linux kernel <linux-kernel@vger.kernel.org>
Subject: Re: Calculating time in order of 0.1usec on x86 system
Date: Tue, 30 Sep 2008 02:37:57 -0700 (PDT)	[thread overview]
Message-ID: <215667.93774.qm@web30102.mail.mud.yahoo.com> (raw)
In-Reply-To: <855204.33912.qm@web30108.mail.mud.yahoo.com>

I am getting my desired numbers.
get_cycles()/cpu_khz gives the right time interval on x86 system.

Parav



--- On Tue, 9/30/08, Parav Pandit <paravpandit@yahoo.com> wrote:

> From: Parav Pandit <paravpandit@yahoo.com>
> Subject: Calculating time in order of 0.1usec on x86 system
> To: "Linux kernel" <linux-kernel@vger.kernel.org>
> Date: Tuesday, September 30, 2008, 12:31 PM
> Hi,
> 
> I need to calculate time spent by a function in order of
> less then a microsecond on x86 SMP platform.
> 
> Current profiling tools and gettimeofday() are not
> sufficient.
> 
> So I am using get_cycles() to get the CPU cycles.
> 
> Now how do I convert it into the time interval?
> 
> Do I have to divide it by "cpu_khz" variable? Or
> some other method?
> Is yes, what will be the unit of the result (time
> interval)? nsec/usec/msec?
> 
> e.g. get_cycles()/cpu_khz (unit?)
> 
> Or Is there more simpler method exist?
> 
> Regards,
> Parav Pandit
> 
> 
>       
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      reply	other threads:[~2008-09-30  9:38 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-30  7:01 Calculating time in order of 0.1usec on x86 system Parav Pandit
2008-09-30  9:37 ` Parav Pandit [this message]

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