From owner-freebsd-hackers@FreeBSD.ORG  Sat Aug  6 09:11:27 2011
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Date: Sat, 6 Aug 2011 09:11:27 +0000
From: Alexander Best <arundel@freebsd.org>
To: Yuri <yuri@rawbw.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: top(1) loses process user time count when threads end
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On Fri Aug  5 11, Yuri wrote:
> I have the process that first runs in 3 threads but later two active 
> threads exit.
> 
> top(1) shows this moment this way (1 sec intervals):
> 30833 yuri            3  76    0  4729M  4225M nanslp  4   0:32 88.62% app
> 30833 yuri            3  76    0  4729M  4225M nanslp  6   0:34 90.92% app
> 30833 yuri            1  96    0  4729M  4225M CPU1    1   0:03  1.17% app
> 30833 yuri            1  98    0  4729M  4226M CPU1    1   0:04 12.89% app
> 
> Process time goes down: 0:34 -> 0:03. Also WCPU goes down 90.92% -> 
> 1.17% even though this process is CPU bound and does intense things 
> right after threads exit.
> 
> getrusage(2) though, called in the process, shows the correct user time.
> 
> I think this is the major bug in the process time accounting.

could you check, whether kern/128177 or kern/140892 describe your situation?

cheers.
alex

> 
> 8.2-STABLE
> 
> Yuri