How to configure powernowd

NOTE!

See the Dynamic Frequency Scaling HOWTO on how to avoid using cpu frequency scaling daemons by using the kernel builtin ondemand governor.

powernowd originally was only written for AMD CPUs which support PowerNow! technology, but it supports other CPUs as well.

Make sure you have loaded the necessary kernel modules. (See How to make use of Dynamic Frequency Scaling)

Installation

On Debian you can do this with:

# apt-get install powernowd

Configuration

Use the sys interface to set the min and max speed:

# echo 825000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

# echo 2200000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq

# /etc/init.d/powernowd start

In Debian you may specify different options for powernowd in /etc/default/powernowd. This file will be loaded by the init script /etc/init.d/powernowd.