Date: Thu, 2 Jul 2015 14:11:26 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Fredrik =?iso-8859-1?Q?Markstr=F6m?= <fredrik.markstrom@gmail.com>
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org,
        Rik van Riel <riel@redhat.com>, Jason Low <jason.low2@hp.com>,
        =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>
Subject: Re: [PATCH 1/1] cputime: Make the reported utime+stime correspond to
 the actual runtime.
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On Tue, Jun 30, 2015 at 08:30:05PM +0200, Fredrik Markstr?m wrote:
> But I don't think the "wobblies" in the division is, since the division doesn't
> affect the sum (prev->stime + prev->rtime) anymore, so that comment should
> go, right ?

Agreed.

> Well I guess it can be a problem on a system where 120 cores are doing nothing
> but hammering on rusage... on the other hand I feel a system like that
> deserves it.  :)

True, doing stupid deserves stupid, but somehow people often tend to
disagree with it when its them doing it :-)

Imagine someone doing a gprof like thing where they stuff a getrusage()
call in the mcount hook and then run their many threaded application.

Provided they use RUSAGE_THREAD it doesn't even sound too insane..
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