Ubuntu – How to set the CPU frequency scaling governor for all cores at once

Just to make sure it's not going to interfere, remove the powernowd package from your system. From a terminal, run:

sudo apt-get remove powernowd

After that, or if you don't have that package installed, install rcconf by running:

sudo apt-get install rcconf

Then run sudo rcconf and press space with the ondemand service highlighted to disable it. This service controls CPU frequency scaling. Press enter to save and quit. To manually stop it once, you can run sudo /etc/init.d/ondemand stop.

I had the same issue on latest version of Mint, setting the scaling to conservative seemed to be the closest to how ondemand used to work.

Then I found out what the problem was, the up_threshold was way too high, it was set to 95% load, now this is fine for continued loads, but in most cases there is a small burst of CPU activity, and you want the CPU to scale to 100% speed much faster. I resolved this by setting th up_threshold lower (75 seems to do OK in my case). You change it by echo'ing the desired value to /sys/devices/system/cpu/cpufreq/ondemand/up_threshold.