Gamer Mode

Live CPU, RAM, and GPU readings in the bar, plus a one-click mode that suspends background resource hogs and restores what was running before.

Requires Noctalia v5 and plugin API 19. Noctalia v4 uses a different QML plugin format and will not list or load this source.

Plugin

Field	Value
ID	nomadcxx/gamer-mode
Entries	Bar widget: gamermode; panel: main; service: service

Requirements

• pgrep and pkill from procps probe and signal process targets
• systemctl controls service and timer targets
• docker controls container targets
• powerprofilesctl from power-profiles-daemon switches the power profile

Each tool matters only if you target that kind. Without powerprofilesctl the panel hides its power row and the toggle still works.

Usage

Gesture	Action
Left-click	Opens the panel. Set Left-click action to toggle to toggle instead.
Right-click	Toggles gamer mode, whatever Left-click action says.

The glyph takes the accent colour while gamer mode runs.

The tooltip carries the live readings:

CPU 25% 59°C | RAM 10.9G | GPU 18% 61°C | VRAM 2.5G

The panel shows a bar per reading, the power profile selector, the suspend profile selector, what the plugin has suspended, and the maintenance actions.

Pick light or heavy in the panel and press Enable, and that profile applies for the session. A plugin reads its own settings and cannot write them, so the choice rides along with the enable rather than changing the Gamer mode profile setting. While gamer mode runs the selector gives way to a label, because the session already fixed the profile. To change it, disable first.

Drive it from a shell or a keybind:

noctalia msg plugin nomadcxx/gamer-mode:service all toggle
noctalia msg plugin nomadcxx/gamer-mode:service all enable
noctalia msg plugin nomadcxx/gamer-mode:service all disable

Toggle the panel:

noctalia msg panel-toggle nomadcxx/gamer-mode:main

Maintenance

Three one-shot cleanups sit at the foot of the panel. None of them is part of gamer mode, and turning gamer mode off does not undo any of them.

Action	What it does	Needs a password
Clear shader caches	Deletes the Mesa, NVIDIA GLCache, RADV, and Steam shader caches	No
Drop page cache	sync, then vm.drop_caches=3	Yes
Reclaim swap	swapoff -a && swapon -a, pulling swapped pages back into RAM	Yes

Clearing shader caches takes two clicks. The first measures and the button reports the size, the second deletes. Games recompile shaders on their next launch, so that launch is slower. This is the one to reach for when a driver update leaves stale shaders behind.

The plugin expands every cache path from a fixed list and drops any that resolves outside your home directory, so the rm only ever sees the paths above, and only those that exist.

Dropping the page cache frees the RAM the kernel uses to cache files. The kernel refills it, and the pages it discards are ones it would otherwise have reused, so this buys less than the number in free suggests.

Reclaiming swap only runs when what is swapped out fits in free RAM with a tenth of total held back. Otherwise it reports that there is no room and does nothing, because succeeding into an out-of-memory kill would defeat the point.

Settings

Setting	Default	Description
Bar icon	device-gamepad-2	Glyph shown in the bar. Names a glyph from the shell's registry.
Left-click action	open_panel	Opens the panel or toggles gamer mode. Right-click toggles either way.
Poll interval	3	Seconds between metric updates: 2, 3, or 5.
Gamer mode profile	light	Selects which target profile a toggle applies.
Auto performance profile	On	Switches to the performance power profile while gamer mode runs, then hands back the previous one.
Show temperatures	On	Includes CPU and GPU temperatures in the tooltip and panel.
Suspend targets (JSON)	Empty	Replaces the built-in target list. See below.

The setting names the profile a bar click applies. The panel selector overrides it for the enable it is sent with, and the bar's right-click toggle does not see that selection, so it uses the setting.

Target list

targets takes a JSON array. Each entry needs a match, a kind, and the profiles it belongs to. action is optional.

[
  {"match": "awww-daemon",     "kind": "process",        "action": "freeze", "profiles": ["light", "heavy"]},
  {"match": "qbittorrent",     "kind": "process",        "action": "freeze", "profiles": ["light", "heavy"]},
  {"match": "ollama.service",  "kind": "system-service", "action": "stop",   "profiles": ["light", "heavy"]},
  {"match": "fstrim.timer",    "kind": "system-timer",   "action": "stop",   "profiles": ["light", "heavy"]},
  {"match": "brave",           "kind": "process",        "action": "freeze", "profiles": ["heavy"]},
  {"match": "jellyfin.service","kind": "system-service", "action": "stop",   "profiles": ["heavy"]}
]

An empty setting uses the built-in list: 173 entries, 94 of them in light. Breadth costs almost nothing, because a target that is not running probes as down, so the plugin never touches it and never restores it. An entry for software you do not have costs one pgrep.

The plugin falls back to the built-in list when the setting holds invalid JSON or when every entry in it fails validation, and logs the reason. It drops single bad entries and honours the rest, so one typo costs you one target.

match compares through pgrep -x, so it needs the whole name. Substrings and patterns do not match. The plugin quotes every value for the shell and refuses a match holding a newline, carriage return, or NUL at parse time.

Actions

action defaults to stop.

	stop	freeze
Mechanism	pkill / systemctl stop / docker stop	SIGSTOP / docker pause
Probes	read-only, never elevated	read-only, never elevated
Frees RAM	Yes	No, pages stay resident
Frees VRAM	Yes	No
Halts CPU use	Yes	Yes
Halts disk I/O	Yes	Yes
Keeps state	No, the target shuts down	Yes, the target resumes where it stopped
Restarts	Units, timers, and containers	Always

Pick freeze for anything you return to: a browser, an editor, a wallpaper daemon. Pick stop when you need the memory back. A local model runtime such as ollama holds VRAM until the service stops, and freezing keeps every VRAM page allocated, so those targets use stop.

Network connections drop while a target sits frozen. That suits a torrent client and hurts a chat app.

Kinds

kind	Probe	stop	Start	freeze	Thaw
process	pgrep -x	pkill -x	none, see below	pkill -STOP -x	pkill -CONT -x
user-service	systemctl --user is-active	systemctl --user stop	systemctl --user start	systemctl --user kill --kill-whom=all -s SIGSTOP	same with SIGCONT
system-service	systemctl is-active	pkexec systemctl stop	pkexec systemctl start	pkexec systemctl kill --kill-whom=all -s SIGSTOP	same with SIGCONT
user-timer	systemctl --user is-active	systemctl --user stop	systemctl --user start	invalid	invalid
system-timer	systemctl is-active	pkexec systemctl stop	pkexec systemctl start	invalid	invalid
container	docker inspect -f '{{.State.Running}}'	docker stop	docker start	docker pause	docker unpause

Timers

Stopping foo.service leaves foo.timer free to fire it again five minutes into your session, so scheduled work needs its own target. A stock Arch install enables fstrim.timer, smartd.timer, paccache.timer, and the package-cache timers, and each one stalls disk I/O mid-game.

The timer kinds require the .timer suffix on match. systemctl is-active fstrim resolves to fstrim.service, so the plugin rejects a timer entry without the suffix at parse time.

Processes do not restart

kind: "process" has no start command. A bare process name carries no argv, no environment, and no working directory, so the plugin cannot relaunch one. That makes process with action: "stop" a one-way trip. The plugin allows it and logs a warning, and every built-in process entry uses freeze. To get something back, target the unit or container that supervises it.

Protected targets

The plugin refuses some targets whatever the setting says, because stopping them ends your session, kills your audio or network, or kills the game gamer mode serves. It drops such an entry at parse time with a logged reason, and every command builder refuses it again at action time, so a session file written by an older version cannot act on one either.

session/display  niri hyprland sway river wayfire labwc gnome-shell kwin_wayland
                 plasmashell Xorg Xwayland greetd sddm gdm
the shell        noctalia quickshell
audio            pipewire pipewire-pulse wireplumber pulseaudio
core IPC         systemd systemd-logind dbus-broker dbus-daemon elogind
network          NetworkManager wpa_supplicant iwd systemd-networkd
game stack       steam steamwebhelper gamescope wine wineserver proton lutris
                 heroic bottles gamemoded

Matching ignores case and any .service, .timer, or .socket suffix, so Steam, steam, and steam.service all fail. The list takes no override. A wrong entry here costs you a dead session or a killed game, and an override field is the one people copy from a forum post without reading. To act on one of these, use Feral GameMode's start= and end= script hooks in gamemode.ini.

System units ask for a password once

Stopping or starting a system unit needs authorisation. The plugin runs all the units of one operation through a single pkexec /usr/bin/systemctl call, which asks once and then does the whole batch as root.

Two simpler approaches were measured first and each cost a password prompt per unit, seven units meaning seven dialogs:

• One systemctl per unit. polkit's auth_admin_keep retains an authorisation against the subject that gave it, and the subject systemd reports is the calling process, so seven processes are seven subjects with nothing to reuse.
• One systemctl naming all seven units. systemctl issues its StopUnit calls in parallel, so every polkit check is outstanding before any of them has an answer, and again nothing can reuse an authorisation that does not exist yet.

org.freedesktop.policykit.exec is auth_admin with no retention, so each pkexec prompts. The built-in targets only ever stop system units and never freeze them, so an enable costs one prompt and a disable costs one. A custom target list that mixes stops and freezes pays one prompt per operation.

Without pkexec the plugin falls back to calling systemctl directly, which still works through systemd's own polkit check at the cost of the prompt-per-unit behaviour. It logs the downgrade at startup.

You need an authentication agent running for any prompt to appear. Most desktops start one; standalone compositors often do not. Check with:

pgrep -af 'polkit.*agent'

If nothing is listed, install one such as mate-polkit, polkit-gnome or hyprpolkitagent and start it with your session. Without an agent the calls fail and each one is logged.

To skip the prompt entirely, grant the units you target. Scope the rule to those units: a blanket rule lets anything running as you stop or start any system unit. In /etc/polkit-1/rules.d/49-gamermode.rules:

polkit.addRule(function (action, subject) {
    var units = ["sonarr.service", "radarr.service", "fstrim.timer"];
    if (action.id == "org.freedesktop.systemd1.manage-units"
        && subject.isInGroup("wheel")
        && units.indexOf(action.lookup("unit")) >= 0) {
        return polkit.Result.YES;
    }
});

Targets left out of the built-in list

Each of these suits someone and makes a poor default. Paste what you want into targets.

Voice chat. Freezing these cuts voice during the activity the plugin serves.

{"match": "discord", "kind": "process", "action": "freeze", "profiles": ["heavy"]},
{"match": "vesktop", "kind": "process", "action": "freeze", "profiles": ["heavy"]},
{"match": "slack", "kind": "process", "action": "freeze", "profiles": ["heavy"]},
{"match": "element-desktop", "kind": "process", "action": "freeze", "profiles": ["heavy"]}

Music. Plenty of people game with music playing.

{"match": "spotify", "kind": "process", "action": "freeze", "profiles": ["heavy"]},
{"match": "spotifyd.service", "kind": "user-service", "action": "stop", "profiles": ["heavy"]},
{"match": "mpd.service", "kind": "user-service", "action": "stop", "profiles": ["heavy"]}

Recording and streaming. Plenty of people stream the game they play.

{"match": "obs", "kind": "process", "action": "freeze", "profiles": ["heavy"]},
{"match": "gpu-screen-recorder", "kind": "process", "action": "freeze", "profiles": ["heavy"]}

Language runtimes. java, dotnet, and node burn CPU, and they run games too. Minecraft and every PrismLauncher or MultiMC instance runs as java. Unity and .NET titles run as dotnet. Freezing those freezes the game. Add them only if nothing you play uses them.

Container and VM daemons. Stopping docker.service takes down every container, and starting it again leaves their previous states behind. Stopping libvirtd kills running guests. Target single containers with kind: "container", which pauses and unpauses through the cgroup freezer.

Shared databases. Other services tend to depend on postgresql, mysqld, and redis. The built-in heavy profile does cover elasticsearch and opensearch, whose JVM heaps often top the RAM table on a development box.

VRAM without stopping the daemon. ollama unloads models while staying up. No target kind covers this, so use a Feral GameMode hook:

[custom]
start=/usr/bin/ollama stop --all

Restore semantics

Enabling writes a session snapshot to the plugin data directory (session.json). For every target in the active profile it records whether the target was running or active or already down, which action applied, the power profile in effect, and the kernel boot ID.

The snapshot lands on disk before anything is suspended. It is the only record of what was running beforehand, so a target suspended without one is unrecoverable: disable would read the session, find none, and return. If the write fails, enabling stops there with the machine untouched and tells you why.

Disable runs two passes, because the two actions need different logic.

The plugin probes each stop target again and starts it back when it is still down. So it leaves alone anything you stopped before enabling gamer mode, and anything you restarted by hand while gamer mode ran. It logs and skips a missing unit or container, and never fails hard partway.

The plugin thaws every freeze target without probing. A frozen process still appears in pgrep, so no probe distinguishes "still frozen" from "running", and SIGCONT to a process that is not stopped exits 0 and changes nothing. Thawing blind beats probing here: it cannot misread a state, cannot stomp a manual restart, and cannot leave something frozen after a probe fails to run.

The snapshot sits on disk, so gamer mode survives a shell restart. Reload Quickshell mid-session and the panel still reports it as on with the same suspend list, and disable still restores.

Enabling twice does nothing. A second enable would re-probe and record the targets it had suspended as "was down", losing what it needs to restore them.

After a reboot

A session file outlives a reboot, so the plugin compares the boot ID at startup. A different ID means the session went stale: nothing that was frozen still exists, and units that were stopped may have come back on their own.

A stale session gets a full restore pass before the plugin clears it. A stopped unit that is not enabled is still down after a reboot, and putting it back is what you were told would happen. Frozen targets died with the reboot, so their thaw does nothing. This can fire a few systemctl start calls soon after login, and the plugin logs each one.

Within the same boot the plugin always keeps the session, even when everything looks like it is running, because that is the case where something may still sit frozen and need thawing. A session written before version 0.2.0 carries no boot ID, and the plugin treats it as current so it does not abandon targets that may still be suspended.

Notes

• The plugin stores its session snapshot in Noctalia's plugin data directory. It makes no network requests.
• renice is absent by design. It looks like the safe middle ground and is not. With RLIMIT_NICE=0, the default, an unprivileged process lowers priority and never raises it back, so a renice would degrade every process it touched for the life of that process. freeze gives you the reversible option instead. Feral GameMode needs membership in a gamemode group to renice at all for the same reason.
• No I/O weighting for user units. cgroup v2 delegates cpu, memory, and pids to the user manager, and not io.
• The bar widget carries the readings in its tooltip. Plugin API 19 does hand a widget onHover(entered), so a richer hover surface is possible and is not built.
• The panel shows no per-core CPU breakdown and no top-process list.
• Nothing places the widget on your bar for you. The manifest has no field for a default bar section, and a plugin can read its settings but not write them, so bar layout stays yours. Add it under Settings → Bar.
• VRAM appears where the shell reports it, which means NVML on NVIDIA.
• The plugin toggles no compositor effects. Animations, blur, and shadows belong to your compositor's own config.
• Feral GameMode exposes a ClientCount property that emits changes and a GameRegistered signal on com.feralinteractive.GameMode, and org.scx.Loader switches sched_ext schedulers. Arming gamer mode from either one would work and is not built.

License

MIT