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From: George Neville-Neil <gnn@neville-neil.com>
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Subject: Re: aperf/mperf
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On Nov 16, 2010, at 09:37 , Andriy Gapon wrote:

>=20
> Many modern processors provide APERF and MPERF MSRs which allow to =
easily and
> reliable calculate average CPU performance level over some interval of =
time.
> This also allows to notice things like performance boost, which is =
generally
> hidden from software.
> What would be a proper place to add code that would measure =
APERF/MPERF ratio?
> When should trigger such a measurement and over what interval?
> Ideas?

Can you point me at documentation for this?   This sounds a lot like
hwpmc(4) and I wonder if we can make these available in the same way.

Best,
George