"limit the clock when screen is off"
I'm always doing that. am I a bad person now?
I know on x86 you Race to idle is what you want but I don't think it behaves just like that on a phone.
When my n4 runs at 1,5 ghz in my pocket, it get's hot. Getting hot means draining the battery, doesn't it?
It takes a lot more power on full speed than on a few hundred mhz and I think this power loss on top speed far outnumbers the time it's not sleeping.
Just like 4 cores on 25% are far more efficient than one core on highest clock.
Found this neato thread about this.http://lwn.net/Articles/281629/
First commet seems about right:
"The dynamic power consumed by a CMOS circuit is proportional to the _square_
of the voltage, while the clock speed is proportional to the voltage itself. Leakage power is constant. So, at least for embedded processors, like ARMs, where leakage power is low, voltage scaling can be a win over sleeping: you halve the speed and power drops by nearly a factor of four."
Then again I wonder why the phone even get's hot.
Ideally there would be no Apps running and then It would be bets to set highest possible speed for short tasks...
A cm wiki mystery team would be awesome!!