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Date: Tue, 08 Jan 2008 13:40:01 -0500
From: Norton Allen <allen AT huarp DOT harvard DOT edu>
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To: Mr Webber <captain_webber AT hotmail DOT com>, cygwin AT cygwin DOT com
Subject: Re: Does clock() work?
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Mr Webber wrote:
> CLOCKS_PER_SEC is a machine dependent macro, but not so machine dependent to
> recognize that my 32-bit windows box has dual processors.  Not useful for
> benchmarking, is it.
>   
It's not quite clear to me why multiple processors would affect the 
interpretation of CLOCKS_PER_SEC, or why such a simple model would not 
work in a single-threaded app for basic benchmarking. I'm not talking 
about a utility to launch commercial apps (which might be multithreaded, 
etc.), just:

    * record the current time
    * do something single-threaded
    * record the current time and calculate elapsed time

> clock is not the way to go. It is a crude estimation of processor time.  On
> regular UNIX times(2) is the function to use -- cygwin does not seem to have
> it.
>   
Any other suggestions for timing resolution better than one second on 
cygwin?

-Norton


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