I started doing some underclocking experiments with the “Kernel Adiutor” app:
play.google.com/store/apps/details?id=com.grarak.kerneladiutor
The kernel might overrule CPU frequency settings and it will not let me disable CPU cores. However, you can set the CPU governor to “power save” which seems to make a difference. The Powersave governor locks the CPU frequency at the lowest frequency set by the user. I have currently set it to 702MHz.
Note: don’t forget to switch on “Apply on boot”.
It’ll take a bit more time to draw conclusions.
Does any of you also play with this? Any good suggestions are highly appreciated
EDIT1: one side effect I noticed after setting slightly more conservative settings is the button responsiveness is getting worse.
Did you root with the latest OTA update that fixed the Wi-Fi MAC address issue?
What was your minimum and maximum speed of the processor your set? I would imagine underclocking anywhere from 800Mhz to 1Ghz should not pose too much of a performance issue. Minimum of 300Mhz or so should be fine, as long as you are setting the CPU governor to “interactive” so it will boost the speed when you are utilizing the watch, and drop it back down for background tasks.
I rooted latest available boot.img
Still testing:
Interactive: fmin = 299MHz fmax = 1001MHz --> could have potential
Tested:
Power save: fmin = 702MHz --> buttons unresponsive, not happy
Interactive governor can indeed extend battery life by a few hours, however it also negatively affects responsiveness (buttons, touch). I will only use it when I really need it. It may be useful to use Tasker to automatically switch to the powersave governor at night time.