[Desire General] th3:
Well, as I mentioned earlier, there are limitations why I don't make or rely on these calcs and software readings as absolutes. They provide us good needed scope for approximations, but that really is how far it goes. When we see consistent unexpected fluctuations then we have some reason to monitor in more detail, but right now, if we were seeking for more data, the best we can establish the impact of an abnormal, high power fluctuation is really only by comparing it between complete discharges.

The effect per hour quite certainly would really depend on the frequency and duration of such spikes. Are they in a fixed, consistent, repetitive pattern every minute, every hour? Or much higher in frequency and duration at some time than another. Do they exist for 30 seconds, 20 seconds... 2 seconds? We don't have any tools to give instantaneous current figures that we can log at least at a per second granularity to work out the full effect of such spikes on complete battery life, per discharge cycle. The Android battery and current monitoring code is giving a) sometimes vague approximations, with many assumptions b) time-averaged readings over what appears to be either the last 30 seconds or higher. Hence we can't establish a) instantaneous current requirements b) the duration of these current fluctuations, nor c) the absolute value of each fluctuation. They could well be much higher in absolute value but shorter in duration. The cell tower switching you actually hypothesize would be a very high absolute power spike although usually momentary. This is all kinda how broadband works by sending out bursts of 100-3 Mbps for small intervals and then resting. At the end of the test, the averaged "speed" value is far smaller than the actual burst speed.

For a full hour, the comparison you suggested could be 11.100 mWh idle compared to 11.695 mWh with the instances you described. So yes, very little net effect if that was an accurate, fixed, recurring state.

Re SetCPU: I just don't understand the logic behind the idea when the OLED display is a vastly bigger battery life determinant. What do people think it's doing better than what Android+the chip already does?

I don't like to tinker with underlying electrical specs outside default operation in small form-factor devices. Many reasons to it but these SLP process chips are heavily tweaked for low static, dynamic and leakage power in every state,including their DVFS timing and skews (and hence latency) heavily tuned for market application-specific performance per power needs. Manipulating any of which can have vast impacts on all three energy consumers as well as the circuits critical timing (hence stability/integrity). Looking at them as just the same as SHP process silicon - like Mobile/Desktop CPUs - that are designed for high voltage/current/frequency ranges as well as much higher absolute switching speeds, and higher clock and PLL skews is just not the reality. Even the fully synthesised circuit floorplan, transistor width, spacing (density) and wire capacitance is heavily tweaked on these SLP, small die, small form-factor ICs. ARM isn't the hotty it currently is for no reason.

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