Kernel - OOM killer in rage, 4 tasks killed

[Dipak Bhoi]

Hello Guys,

I have a VPS server with Centos 6 64bit OS. I had a strange problem on my VPS, that the services like MySQL, Crond, Exim, and Cpanel etc. are getting down after few minutes. After every few minutes I was restarting these services and its work for me only next few minutes

If you are facing same kind of issue and want to get out of from this problem then follow the step as below.

1. Check your server log.
/var/log/messages
/proc/meminfo
/proc/swaps
/proc/vmstat
/proc/vestat

2. I found the logs as follow :

#tail -f /var/log/messages
Jan  8 09:53:47 vps kernel: [19081157.026488] OOM killer in rage, 4 tasks killed
Jan  8 09:53:47 vps kernel: [19081157.026630] OOM killed process 24167 (python) vm:104824kB, rss:9840kB, swap:0kB
Jan  8 09:53:47 vps kernel: [19081157.178766] OOM killer in rage, 2 tasks killed
Jan  8 09:53:47 vps kernel: [19081157.178903] OOM killed process 24172 (python) vm:104828kB, rss:9828kB, swap:0kB
Jan  8 09:53:47 vps kernel: [19081157.247581] OOM killer in rage, 1 tasks killed
Jan  8 09:53:47 vps kernel: [19081157.248339] OOM killer in rage, 1 tasks killed
Jan  8 09:53:47 vps kernel: [19081157.248487] OOM killed process 16304 (cphulkd) vm:43152kB, rss:596kB, swap:3716kB
Jan  8 09:53:48 vps kernel: [19081158.141225] OOM killer in rage, 1 tasks killed
Jan  8 09:53:48 vps kernel: [19081158.141978] OOM killer in rage, 2 tasks killed
Jan  8 09:53:48 vps kernel: [19081158.142122] OOM killed process 16398 (cpanellogd) vm:28964kB, rss:292kB, swap:2088kB

Now you would a question in your mind what is OOM killer ? I had also the same question but after investigating on it I found the following helpful information.

What is OOM killer ?

The Linux kernel has a functionality called Out Of Memory Killer (or OOM Killer) responsible for dealing with memory exhaustion. If system reaches a point where it may soon run out of all memory, OOM Killer looks for a process it could kill and ends its life.

How to get out of this problem ?

OOM killer on the node terminated the init process of the container. To get out off from this problem you have to upgrade your resources like memory and CPU.

For upgrade VPS resources you can check our VPS hosting plans at link https://www.milesweb.com/vps-hosting.php

To learn about OOM or Memory management visit link https://www.kernel.org/doc/Documentation/filesystems/proc.txt

Enjoy!!