I noticed today that a process "ondemand" was running on my Ubuntu Server that I recently upgraded (following the recommended process) from 9.10 to 10.04. Why on earth would they install this by default on a server, and how do I turn it off?
sudo apt-get install cpufrequtils sysfsutils
echo performance | sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
and repeat for every core/CPU you have.
You can verify the result with
To make the change permanent: add the following line (or lines - for several cores/CPUs)
devices/system/cpu/cpu0/cpufreq/scaling_governor = performance
to /etc/sysfs.conf (or edit an already existing line).
You may also have a look at this post.
Most of the solutions provided around the internet are complicated and inefficient since the CPU frequencies reset after a while.
The most simple and 100% solution to disable CPU scaling is:
Uncheck cpufrequtils, loadcpufreq, ondemand, powernowd, powernowd early.
Add CPU frequency scaling monitor to your panel and set your cores to desired frequency.
Check with cpufreq-info that the selected frequency is active all the time (100%).
All your drugs are belong to us! :D