Android CPU Governors Explained – What Do They Do

You have often heard about Android CPU Governors, especially after installing a custom kernel. When you install a custom kernel or even on a stock one, you can use some special apps to overclock and change the CPU governor.

The most usual and popular ones are: OnDemand, Performance, Powersave, LagFree, Hotplug, Pegasuq etc. But what do these governors really do? Why are they so important? Well, a governor controlls the frequency of the CPU and the way it changes. Let’s explain what the governors mentioned above really do.

OnDemand

This is the most used governor on Android devices, especially on smartphones. It is a little biased towards high-frequency clocks, so your phone will be fast, responsive and with a good battery life overall. OnDemand is reliable and well-tested, that’s why it is the stock governor when you install a custom kernel

Performance

As the name says, Performance Governor locks the phone’s CPU at its maximum frequency. Whatever you are doing with your phone, be it an easy task or playing intense video games, the frequency of CPU will always be high. This will allow you for a very quick performance with no stutters at all. However, such a high frequency will drain the battery very quickly.

Powersave

Powesave Governor is the opposite of Perfomance. It will lock the phone’s CPU at the lowest frequency possible. This will be good for battery life but the perfomance will be slow and it will probably stutter a lot.

LagFree

Even though the name is LagFree, this governor will not always provide a smooth performance. It doesn’t skip any frequency step when going down or up, so there will be a latency when going from the lowest to the highest frequency possible. However, this governor provides a very good battery life.

Hotplug

This governor is quite clever when it comes to changing the frequency of the CPU. It is very precise and changes the frequency based on the CPU’s load. An interesting feature of this governor is the ability to turn off unused cores of CPU. So, if you have a quad core phone, only two cores will be turned on if there’s no heavy task to accomplish. This greatly increases battery life.

Lazy

Another interesting governor is Lazy. Lazy Governor has an additional min_time_state parameter. This parameter specifies the amount of time the CPU stays at a frequency before changing to another one. If you open a game or something which requires a lot of power, the CPU will wait for as long as you have specified before going to the highest frequency.

That’s it. These were the most popular governors that you use on your Android device.