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Message-ID: <4D52CEC1.2050605@genband.com>
Date: Wed, 09 Feb 2011 11:28:33 -0600
From: Chris Friesen <chris.friesen@genband.com>
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To: Peter Zijlstra <peterz@infradead.org>
CC: Ingo Molnar <mingo@elte.hu>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: RFC: /proc/<pid>/sched should contain cumulative data for all
 threads in process
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On 02/08/2011 07:45 AM, Peter Zijlstra wrote:
> On Tue, 2011-02-08 at 13:11 +0100, Ingo Molnar wrote:

>> So assuming a tool would want to capture such stats of the system, what would be its 
>> options? Could we do all this via system-wide counters and perf stat alike cheap, 
>> transparent gathering without having to patch/rebuild the kernel?
> 
> Very much depends on what is wanted, but most of the stuff inside those
> files is very specific to the implementation and pinning any of that to
> an ABI is like silly.

Currently we're using the following fields from
/proc/<pid>/task/<tid>/sched:

sum_exec_runtime
wait_sum
wait_max
exec_max
iowait_sum
iowait_count
nr_switches

If there's a better way to get this information (with the precision
available from this interface) then I'd love to hear about it.

Chris

-- 
Chris Friesen
Software Developer
GENBAND
chris.friesen@genband.com
www.genband.com
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