system76-scheduler: add config module (549fd535) · Commits · nix / nixpkgs

nixos/modules/module-list.nix

+1 −0

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		@@ -439,6 +439,7 @@
		./services/desktops/pipewire/wireplumber.nix
		./services/desktops/profile-sync-daemon.nix
		./services/desktops/system-config-printer.nix
		./services/desktops/system76-scheduler.nix
		./services/desktops/telepathy.nix
		./services/desktops/tumbler.nix
		./services/desktops/zeitgeist.nix

nixos/modules/services/desktops/system76-scheduler.nix

0 → 100644

+296 −0

Original line number	Diff line number	Diff line
		{ config, lib, pkgs, ... }:

		let
		cfg = config.services.system76-scheduler;

		inherit (builtins) concatStringsSep map toString attrNames;
		inherit (lib) boolToString types mkOption literalExpression mdDoc optional mkIf mkMerge;
		inherit (types) nullOr listOf bool int ints float str enum;

		withDefaults = optionSpecs: defaults:
		lib.genAttrs (attrNames optionSpecs) (name:
		mkOption (optionSpecs.${name} // {
		default = optionSpecs.${name}.default or defaults.${name} or null;
		}));

		latencyProfile = withDefaults {
		latency = {
		type = int;
		description = mdDoc "`sched_latency_ns`.";
		};
		nr-latency = {
		type = int;
		description = mdDoc "`sched_nr_latency`.";
		};
		wakeup-granularity = {
		type = float;
		description = mdDoc "`sched_wakeup_granularity_ns`.";
		};
		bandwidth-size = {
		type = int;
		description = mdDoc "`sched_cfs_bandwidth_slice_us`.";
		};
		preempt = {
		type = enum [ "none" "voluntary" "full" ];
		description = mdDoc "Preemption mode.";
		};
		};
		schedulerProfile = withDefaults {
		nice = {
		type = nullOr (ints.between (-20) 19);
		description = mdDoc "Niceness.";
		};
		class = {
		type = nullOr (enum [ "idle" "batch" "other" "rr" "fifo" ]);
		example = literalExpression "\"batch\"";
		description = mdDoc "CPU scheduler class.";
		};
		prio = {
		type = nullOr (ints.between 1 99);
		example = literalExpression "49";
		description = mdDoc "CPU scheduler priority.";
		};
		ioClass = {
		type = nullOr (enum [ "idle" "best-effort" "realtime" ]);
		example = literalExpression "\"best-effort\"";
		description = mdDoc "IO scheduler class.";
		};
		ioPrio = {
		type = nullOr (ints.between 0 7);
		example = literalExpression "4";
		description = mdDoc "IO scheduler priority.";
		};
		matchers = {
		type = nullOr (listOf str);
		default = [];
		example = literalExpression ''
		[
		"include cgroup=\"/user.slice/*.service\" parent=\"systemd\""
		"emacs"
		]
		'';
		description = mdDoc "Process matchers.";
		};
		};

		cfsProfileToString = name: let
		p = cfg.settings.cfsProfiles.${name};
		in
		"${name} latency=${toString p.latency} nr-latency=${toString p.nr-latency} wakeup-granularity=${toString p.wakeup-granularity} bandwidth-size=${toString p.bandwidth-size} preempt=\"${p.preempt}\"";

		prioToString = class: prio: if prio == null then "\"${class}\"" else "(${class})${toString prio}";

		schedulerProfileToString = name: a: indent:
		concatStringsSep " "
		(["${indent}${name}"]
		++ (optional (a.nice != null) "nice=${toString a.nice}")
		++ (optional (a.class != null) "sched=${prioToString a.class a.prio}")
		++ (optional (a.ioClass != null) "io=${prioToString a.ioClass a.ioPrio}")
		++ (optional ((builtins.length a.matchers) != 0) ("{\n${concatStringsSep "\n" (map (m: " ${indent}${m}") a.matchers)}\n${indent}}")));

		in {
		options = {
		services.system76-scheduler = {
		enable = lib.mkEnableOption (lib.mdDoc "system76-scheduler");

		package = mkOption {
		type = types.package;
		default = config.boot.kernelPackages.system76-scheduler;
		defaultText = literalExpression "config.boot.kernelPackages.system76-scheduler";
		description = mdDoc "Which System76-Scheduler package to use.";
		};

		useStockConfig = mkOption {
		type = bool;
		default = true;
		description = mdDoc ''
		Use the (reasonable and featureful) stock configuration.

		When this option is `true`, `services.system76-scheduler.settings`
		are ignored.
		'';
		};

		settings = {
		cfsProfiles = {
		enable = mkOption {
		type = bool;
		default = true;
		description = mdDoc "Tweak CFS latency parameters when going on/off battery";
		};

		default = latencyProfile {
		latency = 6;
		nr-latency = 8;
		wakeup-granularity = 1.0;
		bandwidth-size = 5;
		preempt = "voluntary";
		};
		responsive = latencyProfile {
		latency = 4;
		nr-latency = 10;
		wakeup-granularity = 0.5;
		bandwidth-size = 3;
		preempt = "full";
		};
		};

		processScheduler = {
		enable = mkOption {
		type = bool;
		default = true;
		description = mdDoc "Tweak scheduling of individual processes in real time.";
		};

		useExecsnoop = mkOption {
		type = bool;
		default = true;
		description = mdDoc "Use execsnoop (otherwise poll the precess list periodically).";
		};

		refreshInterval = mkOption {
		type = int;
		default = 60;
		description = mdDoc "Process list poll interval, in seconds";
		};

		foregroundBoost = {
		enable = mkOption {
		type = bool;
		default = true;
		description = mdDoc ''
		Boost foreground process priorities.

		(And de-boost background ones). Note that this option needs cooperation
		from the desktop environment to work. On Gnome the client side is
		implemented by the "System76 Scheduler" shell extension.
		'';
		};
		foreground = schedulerProfile {
		nice = 0;
		ioClass = "best-effort";
		ioPrio = 0;
		};
		background = schedulerProfile {
		nice = 6;
		ioClass = "idle";
		};
		};

		pipewireBoost = {
		enable = mkOption {
		type = bool;
		default = true;
		description = mdDoc "Boost Pipewire client priorities.";
		};
		profile = schedulerProfile {
		nice = -6;
		ioClass = "best-effort";
		ioPrio = 0;
		};
		};
		};
		};

		assignments = mkOption {
		type = types.attrsOf (types.submodule {
		options = schedulerProfile { };
		});
		default = {};
		example = literalExpression ''
		{
		nix-builds = {
		nice = 15;
		class = "batch";
		ioClass = "idle";
		matchers = [
		"nix-daemon"
		];
		};
		}
		'';
		description = mdDoc "Process profile assignments.";
		};

		exceptions = mkOption {
		type = types.listOf str;
		default = [];
		example = literalExpression ''
		[
		"include descends=\"schedtool\""
		"schedtool"
		]
		'';
		description = mdDoc "Processes that are left alone.";
		};
		};
		};

		config = {
		environment.systemPackages = [ cfg.package ];
		services.dbus.packages = [ cfg.package ];

		systemd.services.system76-scheduler = {
		description = "Manage process priorities and CFS scheduler latencies for improved responsiveness on the desktop";
		wantedBy = [ "multi-user.target" ];
		path = [
		# execsnoop needs those to extract kernel headers:
		pkgs.kmod
		pkgs.gnutar
		pkgs.xz
		];
		serviceConfig = {
		Type = "dbus";
		BusName= "com.system76.Scheduler";
		ExecStart = "${cfg.package}/bin/system76-scheduler daemon";
		ExecReload = "${cfg.package}/bin/system76-scheduler daemon reload";
		};
		};

		environment.etc = mkMerge [
		(mkIf cfg.useStockConfig {
		# No custom settings: just use stock configuration with a fix for Pipewire
		"system76-scheduler/config.kdl".source = "${cfg.package}/data/config.kdl";
		"system76-scheduler/process-scheduler/00-dist.kdl".source = "${cfg.package}/data/pop_os.kdl";
		"system76-scheduler/process-scheduler/01-fix-pipewire-paths.kdl".source = ../../../../pkgs/os-specific/linux/system76-scheduler/01-fix-pipewire-paths.kdl;
		})

		(let
		settings = cfg.settings;
		cfsp = settings.cfsProfiles;
		ps = settings.processScheduler;
		in mkIf (!cfg.useStockConfig) {
		"system76-scheduler/config.kdl".text = ''
		version "2.0"
		autogroup-enabled false
		cfs-profiles enable=${boolToString cfsp.enable} {
		${cfsProfileToString "default"}
		${cfsProfileToString "responsive"}
		}
		process-scheduler enable=${boolToString ps.enable} {
		execsnoop ${boolToString ps.useExecsnoop}
		refresh-rate ${toString ps.refreshInterval}
		assignments {
		${if ps.foregroundBoost.enable then (schedulerProfileToString "foreground" ps.foregroundBoost.foreground " ") else ""}
		${if ps.foregroundBoost.enable then (schedulerProfileToString "background" ps.foregroundBoost.background " ") else ""}
		${if ps.pipewireBoost.enable then (schedulerProfileToString "pipewire" ps.pipewireBoost.profile " ") else ""}
		}
		}
		'';
		})

		{
		"system76-scheduler/process-scheduler/02-config.kdl".text =
		"exceptions {\n${concatStringsSep "\n" (map (e: " ${e}") cfg.exceptions)}\n}\n"
		+ "assignments {\n"
		+ (concatStringsSep "\n" (map (name: schedulerProfileToString name cfg.assignments.${name} " ")
		(attrNames cfg.assignments)))
		+ "\n}\n";
		}
		];
		};

		meta = {
		maintainers = [ lib.maintainers.cmm ];
		};
		}