Nomad reserved memory & CPU

Nomad reserved memory & CPU "OOM killed" issue

Fix the issue where Nomad reserves too much memory or CPU which results in tasks being killed by OOMKill.

Roman Zipp, April 24th, 2023

I recently ran into an issue where Nomad has reserved too much CPU & memory althoough configured otherwise. This can result in tasks being killed by the OOMKill.

OOM Killed


There is a workaround by overriding the available memory and/or CPU power in your Nomad client config file.

Nomad client config

You can compute your "real" CPU compute power by multiplying the number of cores with the MHz. Example: 4 core CPU with 2 GHz each = 4 * 2000 = 8000.

To get your CPUs clock speed, use the lscpu util:

lscpu | grep MHz

The Nomad client config is located at /etc/nomad/nomad.hcl by default.

client {
  memory_total_mb = 16000
  cpu_total_compute = 8000