Message-ID: <40901E1A.9020904@nortelnetworks.com>
Date: Wed, 28 Apr 2004 17:11:54 -0400
From: Chris Friesen <cfriesen@nortelnetworks.com>
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To: john stultz <johnstul@us.ibm.com>
CC: Christoph Pohl <christoph.pohl@inf.tu-dresden.de>,
       lkml <linux-kernel@vger.kernel.org>
Subject: Re: Low bogomips on IBM x445 (kernel 2.6.5)
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john stultz wrote:

> This is expected. Since the IBM x440/x445 are NUMA systems, we cannot
> use the TSC (cpu cycle counter) as a time source. Instead we use an off
> chip performance counter which runs at 100Mhz. This then translates to a
> bogoMIPS value of ~200. 

That sounds very strange.  Bogomips is supposed to be how many busy-wait loops the cpu can do in a 
second, or at least that's what I've seen in all the books.  It shouldn't matter what the time 
source is.

I would expect a NUMA machine to have different bogomips values for the different CPUs, but the 
values should still be the same as if that cpu was on a uniprocessor system, no?

Chris
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