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[Paul Szabo <psz@xxxxxxxxxxxxxxxxx>]

Expired? That is weird... how come it did not expire between comments#18
and comments#19, between 16Jan and 6Aug?

Anyway the bug is "alive"... as anyone could easily test, with a simple

  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'

On any PAE machine (any amount of RAM, any version userland code, and
any version kernel, I tested many), that should produce an OOM in a
minute or so. Conversely: does anyone have a PAE machine where the
above does not produce an OOM?

Yes I know I promised to test "latest development and upstream" or
somesuch. Sorry I did not get around to it, yet: the test would be
rather disruptive on my home computer.

I also note the suggestion (from kernel developers?) in the references
above, to use amd64 kernel even with 32-bit userland. Maybe Ubuntu could
follow suit.

Cheers, Paul

-- 
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https://bugs.launchpad.net/bugs/1098961

Title:
  PAE regression: OOM with just a few sleeps

Status in “linux” package in Ubuntu:
  Expired

Bug description:
  There is a spurious OOM issue with PAE kernel: it will suffer an OOM
  crash just by running a few processes.
  Please see also
    http://bugs.debian.org/695182
  and discussion on linux-mm@xxxxxxxxx e.g.
    http://marc.info/?l=linux-mm&m=135801969519193&w=2
  I wonder whether
    https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1098342
  is related.

  The issue is a regression with PAE, reproduced and verified 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@xxxxxxxxxxxxxxxxx   http://www.maths.usyd.edu.au/u/psz/
  School of Mathematics and Statistics   University of Sydney    Australia
  --- 
  AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
  AplayDevices:
   **** List of PLAYBACK Hardware Devices ****
   card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog]
     Subdevices: 1/1
     Subdevice #0: subdevice #0
  ApportVersion: 2.0.1-0ubuntu15.1
  Architecture: i386
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  psz        2190 F.... pulseaudio
  CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found.
  Card0.Amixer.info:
   Card hw:0 'Intel'/'HDA Intel at 0xdfddc000 irq 45'
     Mixer name	: 'SigmaTel STAC9227'
     Components	: 'HDA:83847618,102801dd,00100201'
     Controls      : 38
     Simple ctrls  : 21
  CurrentDmesg: [   28.160013] eth0: no IPv6 routers present
  DistroRelease: Ubuntu 12.04
  HibernationDevice: RESUME=UUID=9d2bf7ac-9b0a-4082-ac45-f4d3c8e32c23
  IwConfig:
   lo        no wireless extensions.
   
   eth0      no wireless extensions.
  MachineType: Dell Inc. Dell DM061
  MarkForUpload: True
  Package: linux (not installed)
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
   LANG=C
   SHELL=/bin/bash
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: root=/dev/mapper/isw_cheedcedhh_DadMirroredTB4 ro quiet splash
  ProcVersionSignature: Ubuntu 3.2.0-35.55-generic-pae 3.2.34
  RelatedPackageVersions:
   linux-restricted-modules-3.2.0-35-generic-pae N/A
   linux-backports-modules-3.2.0-35-generic-pae  N/A
   linux-firmware                                1.79.1
  RfKill:
   
  Tags:  precise
  Uname: Linux 3.2.0-35-generic-pae i686
  UpgradeStatus: Upgraded to precise on 2012-04-27 (260 days ago)
  UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
  WifiSyslog: Jan 13 06:42:46 DellE520 NetworkManager[1384]: <info> Unmanaged Device found; state CONNECTED forced. (see http://bugs.launchpad.net/bugs/191889)
  WpaSupplicantLog:
   
  dmi.bios.date: 03/23/2007
  dmi.bios.vendor: Dell Inc.
  dmi.bios.version: 2.2.1
  dmi.board.name: 0WG864
  dmi.board.vendor: Dell Inc.
  dmi.chassis.type: 6
  dmi.chassis.vendor: Dell Inc.
  dmi.modalias: dmi:bvnDellInc.:bvr2.2.1:bd03/23/2007:svnDellInc.:pnDellDM061:pvr:rvnDellInc.:rn0WG864:rvr:cvnDellInc.:ct6:cvr:
  dmi.product.name: Dell DM061
  dmi.sys.vendor: Dell Inc.

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