The backlight udev worker thread called enumerate_devices() on every epoll_wait timeout, i.e. once per polling interval. enumerate_devices() runs udev_enumerate_scan_devices(), which walks the entire /sys/class/backlight and /sys/class/leds trees and opens/closes the sysfs root and every device path. With no `interval` configured the module polls on its default cadence, so this full re-scan ran continuously even when brightness never changed, flooding the filesystem (observed via fatrace as constant open/close of `/`). Raising `interval` only lowered the cadence, which is why the reporter's `interval: 10` workaround reduced the flood. The full re-enumeration is redundant: the udev monitor already delivers change/add/remove events for the backlight and leds subsystems. On the timeout path, re-read only the sysfs attributes of the devices already tracked (via udev_device_new_from_subsystem_sysname) instead of re-scanning the whole tree. This keeps periodic refresh working for firmware backlights such as acpi_video that may not emit udev change events, while eliminating the tree-wide scan. Device discovery of new/removed devices continues through the udev monitor. Fixes #5020.
Waybar
Highly customizable Wayland bar for Sway and wlroots-based compositors.
Available in all major distributions.
Installation · Wiki · Configuration · Styling · Examples · FAQ
Features
Compositor integration
| Compositor | Workspaces / Tags | Window | Layout | Language | Mode |
|---|---|---|---|---|---|
| Sway | ✅ | ✅ | ✅ | ✅ | |
| River | ✅ | ✅ | ✅ | ✅ | |
| Hyprland | ✅ | ✅ | ✅ | ✅ | |
| Niri | ✅ | ✅ | ✅ | ||
| Mango | ✅ | ✅ | ✅ | ✅ | ✅ |
| DWL | ✅ | ✅ | |||
| Wayfire | ✅ | ✅ |
DWL requires the dwl IPC patch.
Modules
- Power & hardware — Battery, UPower, Power profiles daemon, Backlight, CPU, Memory, Disk, Temperature
- Connectivity — Network, Bluetooth, GPS, WWAN
- Audio & media — PulseAudio, WirePlumber, JACK, sndio, Cava, MPD, MPRIS
- Desktop — Clock & calendar, System tray, Idle inhibitor, Keyboard state, Privacy, Gamemode, Systemd failed units, Image, Custom scripts
…and more. Every module is documented on the wiki (see the Modules sidebar).
Getting started
git clone https://github.com/Alexays/Waybar
cd Waybar
meson setup build
ninja -C build
./build/waybar # run without installing
Waybar launches with a sensible default config. To make
it yours, copy the default config and stylesheet into ~/.config/waybar/ and edit
them. The Configuration
and Styling guides cover every
option, and Examples has
ready-to-use community setups.
Installation
Waybar is packaged by most distributions:
An Ubuntu PPA with more recent versions is available here.
Building from source
git clone https://github.com/Alexays/Waybar
cd Waybar
meson setup build
ninja -C build
ninja -C build install # optional
Runtime dependencies
gtkmm3 jsoncpp libsigc++ fmt wayland
chrono-date spdlog xkbregistry libgtk-3-dev upower
libpulse [Pulseaudio module]
libnl [Network module]
libappindicator-gtk3 [Tray module]
libdbusmenu-gtk3 [Tray module]
libmpdclient [MPD module]
libsndio [sndio module]
libevdev [KeyboardState module]
Build dependencies
cmake meson scdoc wayland-protocols
Install dependencies — Ubuntu
sudo apt install \
clang-tidy gobject-introspection libdbusmenu-gtk3-dev libevdev-dev \
libfmt-dev libgirepository1.0-dev libgtk-3-dev libgtkmm-3.0-dev \
libinput-dev libjsoncpp-dev libmpdclient-dev libnl-3-dev libnl-genl-3-dev \
libpulse-dev libsigc++-2.0-dev libspdlog-dev libwayland-dev scdoc upower \
libxkbregistry-dev
Install dependencies — Arch
pacman -S --asdeps \
gtkmm3 jsoncpp libsigc++ fmt wayland chrono-date spdlog gtk3 \
gobject-introspection libgirepository libpulse libnl libappindicator-gtk3 \
libdbusmenu-gtk3 libmpdclient sndio libevdev libxkbcommon upower meson \
cmake scdoc wayland-protocols glib2-devel
Contributing
Contributions are welcome — see CONTRIBUTING.md. The style guidelines are Google's C++ style.
Docs live in the man pages. Module documentation is written in
man/(scdoc) and auto-synced to the wiki. Edit the man page, not the wiki — see.github/wiki.
Caution
Distributions of Waybar are only released on the official GitHub page.
Waybar does not have an official website. Do not trust any site claiming to be official.
License
Waybar is licensed under the MIT license. See LICENSE for details.
