nixpkgs/nixos/modules/services/system/earlyoom.nix
2017-03-24 23:16:16 +01:00

96 lines
2.7 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
ecfg = config.services.earlyoom;
in
{
options = {
services.earlyoom = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Enable early out of memory killing.
'';
};
freeMemThreshold = mkOption {
type = types.int;
default = 10;
description = ''
Minimum of availabe memory (in percent).
If the free memory falls below this threshold and the analog is true for
<option>services.earlyoom.freeSwapThreshold</option>
the killing begins.
'';
};
freeSwapThreshold = mkOption {
type = types.int;
default = 10;
description = ''
Minimum of availabe swap space (in percent).
If the available swap space falls below this threshold and the analog
is true for <option>services.earlyoom.freeMemThreshold</option>
the killing begins.
'';
};
useKernelOOMKiller= mkOption {
type = types.bool;
default = false;
description = ''
Use kernel OOM killer instead of own user-space implementation.
'';
};
ignoreOOMScoreAdjust = mkOption {
type = types.bool;
default = false;
description = ''
Ignore oom_score_adjust values of processes.
User-space implementation only.
'';
};
enableDebugInfo = mkOption {
type = types.bool;
default = false;
description = ''
Enable debugging messages.
'';
};
};
};
config = mkIf ecfg.enable {
assertions = [
{ assertion = ecfg.freeMemThreshold > 0 && ecfg.freeMemThreshold <= 100;
message = "Needs to be a positive percentage"; }
{ assertion = ecfg.freeSwapThreshold > 0 && ecfg.freeSwapThreshold <= 100;
message = "Needs to be a positive percentage"; }
{ assertion = !ecfg.useKernelOOMKiller || !ecfg.ignoreOOMScoreAdjust;
message = "Both options in conjunction do not make sense"; }
];
systemd.services.earlyoom = {
description = "Early OOM Daemon for Linux";
wantedBy = [ "multi-user.target" ];
serviceConfig = {
StandardOutput = "null";
StandardError = "syslog";
ExecStart = ''
${pkgs.earlyoom}/bin/earlyoom \
-m ${toString ecfg.freeMemThreshold} \
-s ${toString ecfg.freeSwapThreshold} \
${optionalString ecfg.useKernelOOMKiller "-k"} \
${optionalString ecfg.ignoreOOMScoreAdjust "-i"} \
${optionalString ecfg.enableDebugInfo "-d"}
'';
};
};
};
}