depot/nixos/modules/hardware/ksm.nix
Luke Granger-Brown 57725ef3ec Squashed 'third_party/nixpkgs/' content from commit 76612b17c0ce
git-subtree-dir: third_party/nixpkgs
git-subtree-split: 76612b17c0ce71689921ca12d9ffdc9c23ce40b2
2024-11-10 23:59:47 +00:00

35 lines
924 B
Nix

{ config, lib, ... }:
let
cfg = config.hardware.ksm;
in {
imports = [
(lib.mkRenamedOptionModule [ "hardware" "enableKSM" ] [ "hardware" "ksm" "enable" ])
];
options.hardware.ksm = {
enable = lib.mkEnableOption "Linux kernel Same-Page Merging";
sleep = lib.mkOption {
type = lib.types.nullOr lib.types.int;
default = null;
description = ''
How many milliseconds ksmd should sleep between scans.
Setting it to `null` uses the kernel's default time.
'';
};
};
config = lib.mkIf cfg.enable {
systemd.services.enable-ksm = {
description = "Enable Kernel Same-Page Merging";
wantedBy = [ "multi-user.target" ];
script =
''
echo 1 > /sys/kernel/mm/ksm/run
'' + lib.optionalString (cfg.sleep != null)
''
echo ${toString cfg.sleep} > /sys/kernel/mm/ksm/sleep_millisecs
'';
};
};
}