Re: quick overview of the perfmon2 interface

From: Tony Luck
Date: Tue Dec 20 2005 - 13:04:18 EST


> > The interface also supports automatic randomization of the reset value
> > for a PMD after an overflow.
>
> Why would one want to randomise the PMD after an overflow?

To get better data. Using a constant reload value may keep measuring the
same spot in the application if you are using a sample frequency that
matches some repeat pattern in the application (and Murphy's law says
that you'll hit this a lot).

-Tony
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