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Date: Wed, 1 Aug 2007 10:52:23 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Andi Kleen <andi@firstfloor.org>
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Subject: Re: [PATCH 2/7] Simple Performance Counters: x86_64 support
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On Wed, 1 Aug 2007, Andi Kleen wrote:

> Christoph Lameter <clameter@sgi.com> writes:
> 
> > Export cycles_to_ns (after renaming the cycles_2_ns to cycles_to_ns to be
> > conforming to other arches).
> 
> This function is broken in some cases (e.g Opteron with powernow or
> AMD dual core or older Intel systems) and going away.  The TSCs tick
> with different frequencies on different CPU there. In general i would
> recommend to only report cycles.

But then the numbers are not comparable across systems.