How Android "P" optimises battery usage


(Simon B) #1

This is a really good article, with some interviews with Android engineers :grinning:


(Michael) #2

Hard to tell how much it helps on a Pixel 1, at least it’s not being throttled!

Struggling a bit on P though with the GPS being completely out of whack, works fine for driving, but maps for walking about is useless at the moment :frowning:


#3

The throttling was so maligned but such a sensible idea.

As batteries age the internal impedance rises, so if the same current is drawn the voltage drops more. Modern CPUs are run extremely close to their dropout voltage to save power and heat, so this additional voltage drop would cause them to crash.

So throttling back the current requirement by slowing them down would mean they run more reliably.


#4

(Simon B) #5

This happened to me last Thursday! Turns out I was actually grateful for it, as I was out all day and it meant that my battery lasted long enough to get me home :joy:


(Michael) #6

I’m not convinced it works very well tbh. My phone (Pixel 1) lasted all day on the early dev previews, now its dead by early afternoon.