Re: [patch 0/3] [Announcement] Performance Counters for Linux

From: Arjan van de Ven
Date: Fri Dec 05 2008 - 09:59:48 EST

On Fri, 05 Dec 2008 00:07:16 -0800 (PST)
David Miller <davem@xxxxxxxxxxxxx> wrote:

> These things aren't measuring time, or even just cycles, they
> are measuring things like L2 cache misses, cpu cycles, and
> other similar kinds of events.
> So these counters are going to measure all of the damn crap
> assosciated with doing the read() call as well as the real work
> the task does.

as you said before, not if you do the read() from a thread that's
exempt from the profiling.

Arjan van de Ven Intel Open Source Technology Centre
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