aperf/mperf

George Neville-Neil gnn at neville-neil.com
Thu Nov 18 04:26:48 UTC 2010


On Nov 16, 2010, at 09:37 , Andriy Gapon wrote:

> 
> 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



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