Earlyoom doesn't work

[SamLukeYes]

Describe the bug

I enabled earlyoom, but it doesn't trigger under high memory pressure, and the kernel OOM killer activated instead.

Steps To Reproduce

Steps to reproduce the behavior:

1. Enable earlyoom
2. Make sure earlyoom is running by systemctl status earlyoom
3. Run tail /dev/zero
4. Check earlyoom's log by journalctl -u earlyoom | grep sending

Expected behavior

Earlyoom kills the process and logs something like Feb 20 10:59:34 debian earlyoom[10231]: sending SIGTERM to process 7378 uid 1000 "tail": oom_score 156, VmRSS 4962 MiB, as explained in its README.

Screenshots

Additional context

I also have zramSwap.enable = true set. Not sure whether it is relevant.

Notify maintainers

@AndersonTorres

Metadata

• system: "x86_64-linux"
• host os: Linux 6.6.28-xanmod1, NixOS, 24.05 (Uakari), 24.05pre-git
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.18.2
• nixpkgs: /etc/nix/inputs/nixpkgs

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[SamLukeYes]

It seems this issue is related to xanmod kernel. Switched to the default kernel and the issue is gone.

However, the following test doesn't reproduce the issue 😕

{ nixpkgs ? <nixpkgs> }:

let
  pkgs = import nixpkgs {};
in
pkgs.testers.runNixOSTest {
  name = "earlyoom";

  nodes.machine = {
    boot.kernelPackages = pkgs.linuxPackages_xanmod;
    services.earlyoom = {
      enable = true;
    };
    zramSwap.enable = true;
  };

  testScript = ''
    cmd = "tail /dev/zero"
    machine.wait_for_unit("earlyoom.service")
    machine.execute(cmd, timeout = 30)
    machine.succeed(f"journalctl -u earlyoom.service | grep '{cmd}'")
  '';
}