mailx swapped heavily until mouse and keyboard went unresponsive

[Bremm]

Binary package hint: bsd-mailx

I just ran this script http://counter.li.org/scripts/machine-update and suddenly my linux box started to thrash leading to a unresponsive system. I had to kill it using Alt+SysRq+S|U|B to reboot.

At /var/log/syslog.1 I've seen several lines like these:

May 4 21:30:43 host kernel: [1282828.125203] [17196] 1000 17196 1575 35 0 0 0 mailx
May 4 21:30:43 host kernel: [1282828.125208] [17197] 1000 17197 1575 37 0 0 0 mailx
May 4 21:30:43 host kernel: [1282828.125216] [17199] 1000 17199 1575 35 0 0 0 mailx
May 4 21:30:43 host kernel: [1282828.125220] [17200] 1000 17200 1540 17 0 0 0 mailx

I hope it isn't related to preload daemon.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: bsd-mailx 8.1.2-0.20100314cvs-1 [modified: usr/bin/bsd-mailx]
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Wed May 4 22:53:30 2011
ProcEnviron:
 LANGUAGE=pt_BR:en
 PATH=(custom, no user)
 LANG=pt_BR.UTF-8
 SHELL=/bin/bash
SourcePackage: bsd-mailx
UpgradeStatus: Upgraded to natty on 2011-03-15 (50 days ago)

[Bremm (bremm)]

I left htop opened, a new console also (two different windows) and before run the script I just set some new limits:

$ ulimit -d 100000 -m 100000 -v 100000

It's preload combined with mailx doing all the fuss. I'll try to run mailx with proload off or make preload ignore it.

[Bremm (bremm)]

I did a different approach this time. Only capped the number of processes a user can run.

$ ulimit -u 512

$ nice -n 19 ./machine-update -m
send-mail: fork: Resource temporarily unavailable

bsd-mailx is acting like a fork bomb or whatever.

[Serge Hallyn (serge-hallyn)]

Please reply if this is still an issue on a supported release.