you will save power by letting the run fast, to get a job done, and then it can drop to a low power idle mode. search "matthew garrett power management" for some good blog posts and videos.

i imagine this is even more true on an arm cpu (compared to desktop/laptop cpus), as it have very low power idle modes.

if you have things running in the background using cpu, they are either along the lines of
* sleep for n milliseconds/seconds/minutes, do something, sleep again
* run as fast as possible all the time

the first case, the soon the job can finish, the sooner you can save power again.

the second case will drain your battery pretty quick no matter what you do.

has anyone tried running powertop on an IT