Out-of-memory behaviour

Ask Fedora
1

Hello,

as far as i undestand the OOM killer (in fedoras case its systemd-oomd) should kill some user space process before running out of memory to prevent a system lock-up.

However for me it doesn’t do it or does it after the system was hanging for quite a while. This is quite frustrating.

To reproduce:

DON’T DO THIS IF YOU DONT WANT YOUR SYSTEM TO HANG

Run tail /dev/zero the process eats up your whole memory and the system hangs and then after about 30 seconds it gets killed by the kernel oomkiller instead of systemd-oomd.

This is quite confusing to me why it isnt killing it faster.

Do you have any ideas what might be the issue and what should be configured to stop the system from hanging?

2

The oom killer may not be able to kill processes fast enough to prevent issues.

If this keeps happening to you then run less apps at the same time or add memory to your system to stop this from happening.