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From: Peter Chubb <peter@chubb.wattle.id.au>
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Date: Mon, 12 May 2003 15:04:09 +1000
To: William Lee Irwin III <wli@holomorphy.com>
Cc: Robert Love <rml@tech9.net>, Chris Friesen <cfriesen@nortelnetworks.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: how to measure scheduler latency on powerpc?  realfeel doesn't work due to /dev/rtc issues
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>>>>> "William" == William Lee Irwin, <William> writes:
William> Not at all. Just stamp at wakeup and difference when it runs.


That then doesn't include interrupt latency.  The nice thing about the
amlat tests is that the test predicts when the next interrupt should
occur, then measures the time between that prediction and the process
running in userspace.  If you just timestamp at wakeup, you miss all
the time between interrupt generation and noticing that the process is
to wake up.

--
Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
You are lost in a maze of BitKeeper repositories,   all slightly different.
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