choomd

Adjust process OOM-killer scores based on process names and other attributes

Arch Linux: https://aur.archlinux.org/packages/choomd-git

Edit /etc/choomd.toml to your liking, for example:

# Sacrifice firefox tabs before the browser

[rules.firefox-contentproc]
command_line_file_name = [ 'firefox', 'firefox-bin' ]
command_line_argument = [ '-contentproc' ]
oom_score_adj = 500

[rules.firefox]
command_line_file_name = [ 'firefox', 'firefox-bin' ]
oom_score_adj = 450

More on configuration here: https://github.com/futpib/choomd/blob/master/etc/choomd.toml

Enable the service:

systemctl enable --now choomd

RUST_LOG=debug choomd --config-file ./choomd.toml

Avoid setting negative or low (< 200) oom_score_adj as you may create an unkillable monster

• Alt+SysRq+f kernel hotkey that triggers OOM killer
• OOMPolicy and DefaultOOMPolicy systemd options that make systemd terminate siblings of an OOM-killed process
• OOM htop column to see which processes are next in line for the OOM kill

Change OOM daemon. By analogy with choom command.