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Subject: Re: [PATCH] kprobes for s390 architecture
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
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To: Mike Grundy <grundym@us.ibm.com>
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Date: Tue, 11 Jul 2006 16:13:18 +0200
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On Tue, 2006-07-11 at 09:54 -0400, Mike Grundy wrote:
> I did a little measuring. On average stop_machine_run() adds 8.7 msec of
> overhead on a 4-way config. Of that %57 was sub-msec overhead. For the times
> where overhead was measurable, the average was 20.2 msec, lowest at 10msec
> highest at 100msec. That's on a z800 under vm and I have no idea how many real
> cpus the machine has :-)

So adding 100 probes will roughly take 1 second. Not too bad, I expected it
to take longer.

-- 
blue skies,
  Martin.

Martin Schwidefsky
Linux for zSeries Development & Services
IBM Deutschland Entwicklung GmbH

"Reality continues to ruin my life." - Calvin.