How to use cpufrequtils
NOTE!
See the Dynamic Frequency Scaling HOWTO on how to avoid using cpu frequency scaling daemons by using the kernel builtin ondemand governor.
This package mainly has 2 programs:
- /usr/bin/cpufreq-info
- /usr/bin/cpufreq-set
cpufreq-info gives general device information:
xaiki@gonzo:~$ cpufreq-info
cpufrequtils 0.2: cpufreq-info (C) Dominik Brodowski 2004
Report errors and bugs to linux@brodo.de, please.
analyzing CPU 0:
driver: speedstep-smi
CPUs which need to switch frequency at the same time: 0
hardware limits: 500 MHz - 700 MHz
available frequency steps: 700 MHz, 500 MHz
available cpufreq governors: userspace, performance
current policy: frequency should be within 500 MHz and 700 MHz.
The governor "userspace" may decide which speed to use
within this range.
current CPU frequency is 700 MHz.
and cpufreq-set allows setting ... Never got it working ...
I've got -- you need to get userspace governor active:
- modprobe cpufreq_userspace
- echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
Then cpufreq-set -f 500000 (or 700000) should do the job.