lkml.org 
[lkml]   [2004]   [Aug]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectKernel 2.6.8.1: swap storm of death
Date
I can bring down my box by running a program that does a calloc() of 512Mb 
(which is the size of my RAM). The box starts to heavily swap and never
recovers from it. The process that calloc's the memory gets OOM killed (which
is also strange as I have 1Gb free swap).

After the OOM kill, the shell where I started the calloc() program is alive
but very slow. The box continues to swap and the other processes remain dead.

To gather some more statistics, I did the following:

- start 'vmstat 1|tee vmstat.txt' in 1 VT session.
- run expunge (= program that does calloc(512Mb)) in another VT.

The box freezes for some time. After a while expunge is OOM killed, the vmstat
on the other VT remains dead. A ping over the network is still possible and I
can still start programs on the expunge VT, albeit it is slow as the disk is
still thrashing.



The diagnostics can be found here:

* Kernel .config
http://users.telenet.be/kvogel/config.txt

* expunge program
http://users.telenet.be/kvogel/expunge.c

* vmstat 1 output while executing expunge (this freezes)
http://users.telenet.be/kvogel/vmstat.txt

* vmstat in expunge VT after the OOM kill
http://users.telenet.be/kvogel/vmstat-after-kill.txt

* /proc/slabinfo after OOM kill
http://users.telenet.be/kvogel/slab.txt

* swapon -s
Filename Type Size Used
Priority
/dev/hda3 partition 1044216 0 -1

* Kernel boot line:
kernel /vmlinuz-2.6.8.1 ro root=/dev/compat/root elevator=cfq
voluntary-preempt=3 preempt=1

Kernel was patched with voluntary-preempt-2.6.8.1-P7
syslogd & klogd weren't running and 'dmesg -n 1' was done beforehand.



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:05    [W:0.258 / U:0.548 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site