Comment 4 for bug 1466741

It's not the same as bug 1378126. That one was because the focused app was woken up when the greeter was hidden, thus catching up with everything while the lockscreen was visible. The fix was to only wake up the app when the lockscreen was unlocked. That is still the case, I just verified.

So very likely something else triggers a cpu intensive task when the phone wakes up from deep sleep, processing things while the lockscreen is there.