Ring Monitor

A modern minimal circular system monitor widget for KDE Plasma 6.

Clean 270° ring gauges driven by KSysGuard sensors, themed via the current Plasma color scheme. Built from scratch as a learning project for QML/Qt Quick.

Metrics

• CPU — usage (with optional per-core concentric inner rings) and temperature
• Memory — RAM and swap (zram included)
• GPU — usage and temperature
• Disk — per-partition usage rings; mounted removable drives are shown automatically

Temperatures render as a half-arc and can optionally be merged into their usage ring; the unit follows your locale (°C / °F).

Features

• Themed to your desktop — follows the current Plasma color scheme, or set custom accent and text colors with separate light- and dark-mode values.
• Layout — horizontal or vertical, with adjustable track / arc / text opacity.
• Reorder & toggle — drag rings to reorder, click to show or hide, all from the config dialog.
• Update notifications — an in-widget badge when a newer release is published on GitHub (can be turned off in settings).
• Standalone build — a native Qt/QML binary for non-KDE desktops (see below).

Install

KDE Plasma 6 (recommended: KDE Store)

The easiest way — no terminal, and Plasma will offer updates:

1. Right-click the desktop or a panel → Add Widgets…
2. Click Get New Widgets… → Download New Plasma Widgets.
3. Search for Ring Monitor, then Install.

It's then available in the Add Widgets panel. The widget is published on the KDE Store at https://www.opendesktop.org/p/2360410 — you can also browse the page there directly.

Manual install (from source)

If you've cloned the repo (e.g. to run an unreleased version), install the package straight from the working tree:

kpackagetool6 -t Plasma/Applet -i .

Then add "Ring Monitor" via Plasma's "Add Widgets" panel. Use kpackagetool6 -t Plasma/Applet -u . to update an existing install.

Standalone (non-KDE desktops)

A native Qt/QML build runs the same rings as a frameless desktop widget on non-KDE desktops, with no Plasma shell, libksysguard, or KConfig dependency (issue #7). It reads metrics directly from /proc, sysfs, and NVML.

Status: work in progress. On wlroots / KWin Wayland the widget runs as a native wlr-layer-shell bottom-layer surface (no Alt+Tab, click pass-through, survives a desktop click); on X11, GNOME-Wayland, XFCE, and other EWMH stacking WMs it runs as a Conky-style always-on-bottom window (via XWayland on Wayland-GNOME). Tiling WMs are out of scope for now.

Install via AppImage (any Linux)

The easiest path — one file, no toolchain, no runtime dependencies (Qt 6 + Kirigami are bundled, and it's built on an older glibc for broad distro compatibility). Download Ring_Monitor-<version>-x86_64.AppImage from the latest release, then:

chmod +x Ring_Monitor-*-x86_64.AppImage
./Ring_Monitor-*-x86_64.AppImage

NVIDIA GPU support works out of the box (the binary dlopens libnvidia-ml.so.1 at runtime); AMD/Intel GPUs are read from sysfs.

First launch needs the executable bit. Browsers don't preserve it on download, so the file arrives rw-rw-r-- and a double-click in the file manager does nothing (silently — issue #101). The chmod +x above fixes it; in a file manager it's Properties → Permissions → Allow executing as program. On XFCE / Thunar a double-click may still do nothing even after that, because those desktops ship no default handler for the application/vnd.appimage MIME type — run it from the terminal as shown, or install AppImageLauncher.

Add it to your application menu

Once it's running, right-click → Settings → About → "Show in application menu". Ring Monitor writes a launcher to ~/.local/share/applications/ pointing at the AppImage (no root, no system-wide change), so it shows up in your launcher and survives moves of the AppImage as long as the path stays put. Untick it to remove the entry. The neighbouring "Start automatically on login" toggle works the same way via ~/.config/autostart/.

Build from source

Prefer building yourself (or your system lacks FUSE for AppImages)?

Build dependencies: CMake ≥ 3.16, a C++17 compiler, Qt 6.6+ (Core Gui Qml Quick QuickControls2; 6.6 for the Shape.CurveRenderer the rings use), xcb (dev headers) and pkg-config. NVIDIA GPU support needs no build dependency — the standalone binary dlopens libnvidia-ml.so.1 at runtime (absent → the GPU ring simply stays at 0, so the build runs on AMD/Intel boxes too).

# Fedora
sudo dnf install cmake gcc-c++ qt6-qtdeclarative-devel qt6-qtbase-devel libxcb-devel pkgconf
# Debian / Ubuntu
sudo apt install cmake g++ qt6-declarative-dev qt6-base-dev libxcb1-dev pkg-config
# Arch
sudo pacman -S cmake gcc qt6-declarative qt6-base libxcb pkgconf

Build and run:

cmake -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build
./build/ring-monitor-standalone

Right-click the widget for settings. To start it on login, enable "Start on login" in those settings — it writes ~/.config/autostart/dev.manuacl.ringmonitor.desktop (no system-wide install step is required).

Develop

Symlink the repo into Plasma's plasmoid path so edits hot-reload:

ln -s "$PWD" ~/.local/share/plasma/plasmoids/dev.manuacl.ringmonitor

Enable the pre-commit hook (qmlformat + qmllint + 500-line size cap):

git config core.hooksPath .githooks

Run the test suite (Node logic + QML runtime):

tests/run-all.sh

You need qt6-qtdeclarative-devel + kf6-kirigami for qmllint, qmlformat, and qmltestrunner. Windowed Plasma preview (still the Plasma build, not the standalone binary):

plasmawindowed dev.manuacl.ringmonitor

Documentation

In-depth docs live under docs/ (start at the index):

• architecture.md — file roles, core → platforms layering
• components.md — visual components + platform adapters
• logic-modules.md — pure JS modules
• config-dialog.md — Plasma config-dialog gotchas
• adding-a-metric.md — step-by-step
• testing.md — Node + QML test runners
• development.md — symlink, journal, tooling
• releasing.md — release flow + KDE Store upload

License

GPL-3.0-or-later.