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Message-ID: <003501c17dce$b53a8210$7add18ac@amr.corp.intel.com>
From: "Tim Prince" <tprince AT computer DOT org>
To: "Ralf Habacker" <Ralf DOT Habacker AT freenet DOT de>,
   "Cygwin" <cygwin AT sources DOT redhat DOT com>
References: <006401c17cd6$3c9e2fd0$9a5f07d5 AT BRAMSCHE>
Subject: Re: Old Thread: Cygwin Performance
Date: Wed, 5 Dec 2001 12:36:07 -0800
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> > -----Original Message-----
> > From: Tim Prince [mailto:tprince AT computer DOT org]
> > Sent: Sunday, December 02, 2001 10:58 PM
> > To: Ralf Habacker
> > Cc: Cygwin
> > Subject: Re: Old Thread: Cygwin Performance
> >
> >
The QueryPerformance() calls are still giving 1.00 second timing resolution
on an AthlonMP box (should be better than 10 microseconds on most other
boxes, with correct usage), but their use appears to be truer to the
original lmbench than the cygwin gettimeofday() with its 1.00 second
resolution.

I believed there were deficiencies in the way lmbench uses
QueryPerformance(), preserving only 31 bits of clock ticks from the time of
initialization, but I didn't succeed in showing any better way.


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