From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754348Ab3ALTle (ORCPT ); Sat, 12 Jan 2013 14:41:34 -0500 Received: from talus.maths.usyd.edu.au ([129.78.68.1]:43348 "EHLO talus.maths.usyd.edu.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754116Ab3ALTld (ORCPT ); Sat, 12 Jan 2013 14:41:33 -0500 X-smtpdoor-from: psz@maths.usyd.edu.au X-smtpdoor-want-Message-ID: <201301121941.r0CJf5ps017150@como.maths.usyd.edu.au> Date: Sun, 13 Jan 2013 06:41:05 +1100 From: paul.szabo@sydney.edu.au Message-Id: <201301121941.r0CJf5ps017150@como.maths.usyd.edu.au> To: linux-mm@kvack.org Subject: Re: [RFC] Reproducible OOM with just a few sleeps Cc: 695182@bugs.debian.org, linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The issue is a regression with PAE, reproduced and verified on Ubuntu, on my home PC with 3GB RAM. My PC was running kernel linux-image-3.2.0-35-generic so it showed: psz@DellE520:~$ uname -a Linux DellE520 3.2.0-35-generic #55-Ubuntu SMP Wed Dec 5 17:45:18 UTC 2012 i686 i686 i386 GNU/Linux psz@DellE520:~$ free -l total used free shared buffers cached Mem: 3087972 692256 2395716 0 18276 427116 Low: 861464 71372 790092 High: 2226508 620884 1605624 -/+ buffers/cache: 246864 2841108 Swap: 20000920 258364 19742556 Then it handled the "sleep test" bash -c 'n=0; while [ $n -lt 33000 ]; do sleep 600 & ((n=n+1)); ((m=n%500)); if [ $m -lt 1 ]; then echo -n "$n - "; date; free -l; sleep 1; fi; done' just fine, stopped only by "max user processes" (default setting of "ulimit -u 23964"), or raising that limit stopped when the machine ran out of PID space; there was no OOM. Installing and running the PAE kernel so it showed: psz@DellE520:~$ uname -a Linux DellE520 3.2.0-35-generic-pae #55-Ubuntu SMP Wed Dec 5 18:04:39 UTC 2012 i686 i686 i386 GNU/Linux psz@DellE520:~$ free -l total used free shared buffers cached Mem: 3087620 681188 2406432 0 167332 352296 Low: 865208 214080 651128 High: 2222412 467108 1755304 -/+ buffers/cache: 161560 2926060 Swap: 20000920 0 20000920 and re-trying the "sleep test", it ran into OOM after 18000 or so sleeps and crashed/froze so I had to press the POWER button to recover. Cheers, Paul Paul Szabo psz@maths.usyd.edu.au http://www.maths.usyd.edu.au/u/psz/ School of Mathematics and Statistics University of Sydney Australia