Date: Wed, 27 Aug 2003 16:41:01 +0200
From: bert hubert <ahu@ds9a.nl>
To: Andrew Morton <akpm@osdl.org>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] 2.6.0-test4 -- add context switch counters
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On Tue, Aug 26, 2003 at 06:18:07PM -0700, Andrew Morton wrote:

> >  always zero.  The appended patch adds fields to struct task_struct to
> >  count context switches, and adds code to do the counting.

> OK...  Why is this useful?  A bit of googling doesn't show much interest in
> it.

I'm unaware of the cost of accounting this, but I for one have had
occasions where my system was reporting 20kcs, and I had no clue which
process was causing it. After a while I learned that linuxthreads on SMP can
cause this.

> What apps should be reporting this info?  /usr/bin/time?

/proc/$$/stat would also be nice.

Thanks.

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