go-cpu-governor

GTK3-based AppIndicator to select a CPU governor. The application consists of 2 parts:

• A back-end service running with root permissions and exporting a D-Bus system interface com.github.kamilsamaj.CpuGovernor, with a single method com.github.kamilsamaj.CpuGovernor.SetGovernor.
• GTK3 User-space application displayed as an GTK3 AppIndicator menu, calling the com.github.kamilsamaj.CpuGovernor.SetGovernor method.

Build

Prerequisites

• Go
• libappindicator-dev 3.0.1
• gir1.2-appindicator3-0.1
• libgtk-3-dev

Ubuntu 22.04+ replaced the original libappindicator3-dev with libayatana-appindicator3-dev which has a compatible interface and the existing .so objects are symlinked for backwards compatibility but to do the actual compilation of Go's GTK3 bindings, you'll need to symlink also the C header files and create configuration for the pkg-config.

sudo ln -s /usr/include/libayatana-appindicator3-0.1 /usr/include/libappindicator3-0.1
cd /usr/include/libappindicator3-0.1
sudo ln -s libayatana-appindicator libappindicator

# create a config for pkg-config
cat << 'EOF' | sudo tee /usr/lib/x86_64-linux-gnu/pkgconfig/appindicator3-0.1.pc
prefix=/usr
exec_prefix=${prefix}
libdir=${prefix}/lib/x86_64-linux-gnu
bindir=${exec_prefix}/bin
includedir=${prefix}/include

Cflags: -I${includedir}/libappindicator3-0.1
Requires: dbusmenu-glib-0.4 gtk+-3.0
Libs: -L${libdir} -lappindicator3

Name: appindicator3-0.1
Description: Application indicators
Version: 12.10.0

EOF

make build

Install

make install

Check the service status

sudo systemctl status cpu-governor

Check the service logs

journalctl -fu cpu-governor.service

Check the desktop application logs

journalctl -f | grep cpu-indicator.desktop

Send a D-Bus message to the service

The back-end service registers a D-Bus system interface com.github.kamilsamaj.CpuGovernor, with a single method called SetMode. This method requires a string argument of a value:

• powersave
• balancepower
• balanceperformance
• performance

If the D-Bus call is accepted, the same argument value is returned.

Using gdbus to set the CPU performance and energy preference

gdbus call \
    --system \
    --dest com.github.kamilsamaj.CpuGovernor \
    --object-path /com/github/kamilsamaj/CpuGovernor \
    --method com.github.kamilsamaj.CpuGovernor.SetMode \
    <REQUESTED_STATE>

For example, set the powersave CPU Governor with the power CPU Power Preference:

gdbus call \
    --system \
    --dest com.github.kamilsamaj.CpuGovernor \
    --object-path /com/github/kamilsamaj/CpuGovernor \
    --method com.github.kamilsamaj.CpuGovernor.SetMode \
    powersave

Get the current CPU cores' frequency

watch cat /sys/devices/system/cpu/cpu[0-9]*/cpufreq/scaling_cur_freq

Get the current CPU governor

watch cat /sys/devices/system/cpu/cpu[0-9]*/cpufreq/scaling_governor

Troubleshooting

To list and introspect the available D-Bus interfaces, you can install:

sudo apt install -y qtchooser

And run it with:

qdbusviewer

More info

• https://documentation.suse.com/sles/15-SP1/html/SLES-all/cha-tuning-power.html