linux-kernel - Re: bogomips discrepancy on Intel Core2 Quad CPU

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Message-ID: <46DC1E9B.3030108@tmr.com>
Date:	Mon, 03 Sep 2007 10:47:55 -0400
From:	Bill Davidsen <davidsen@....com>
To:	bjdouma@...all.nl
CC:	linux-kernel@...r.kernel.org
Subject: Re: bogomips discrepancy on Intel Core2 Quad CPU

Bauke Jan Douma wrote:
> $> uname -a
> Linux skyscraper 2.6.22.5 #7 SMP PREEMPT Sun Sep 2 12:12:25 CEST 2007 
> i686 GNU/Linux
> 
> $> cat /proc/cpuinfo | grep bogomips
> bogomips    : 4813.46
> bogomips    : 4810.91
> bogomips    : 4810.91
> bogomips    : 10583.94
> 
> The latter seems way off base.
> Prod me for more info.
> 
I see this occasionally on a dual, speedstep (or similar) finds a way to 
throttle down the cores under light load. I suspect that if you load the 
system:

   for n in 1 2 3 4; do
     nice -19 bash -c 'while true; do a=$RANDOM; done' &
   done

Then you should see your bogomips rise on all cores.


> bjd

	[... copy of output snipped, see the O.P. ...]

-- 
Bill Davidsen <davidsen@....com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot
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