The wording on the battery usage screen is: "Battery used by applications when running."
So what does "running" mean? Is it the time when any activity or service of an app is between onResume and onPause? If it means that when my application is consuming CPU resources (e.g., has threads that are active), it drains the battery by X%, then my applicatoin is doing very well, as it has very low totals for CPU usage. The irony here is that one of my application's primary use cases is actually SAVING power. This is done by allowing the phone to blank the screen automatically when the phone is not within an orientation range associated with user interaction. On the other hand, the application keeps the screen on when the phone is being held in an orientation that implies user interaction. This approach works really well, since it effectively allows users to keep an aggressively low screen timeout without being annoyed to death. I'm getting the impression that my implementation of the concept has varying degrees of effectiveness, depending on the hardware platform. Many users of the Hero, for example, have reported dramatic improvements in battery life (anywhere from 20% to 100% improvement), while others claim that the app provides no power savings, while still others claim that it drains battery. I suppose that this may also depend on phone usage patterns, but the ratings for the application are reasonably high (around 4.20 last time I checked) On Oct 8, 3:15 pm, Romain Guy <[email protected]> wrote: > I would have to check but 40% does not mean that your app used 40% of > the battery but that your app was responsible for 40% of the battery > consumption. Even if that consumption was only 3% of the total battery > capacity. > > > > > > On Thu, Oct 8, 2009 at 11:41 AM, dadical <[email protected]> wrote: > > > I am indeed sleeping (I'll check out the other threads, thanks for the > > tip). From a battery usage perspective, I can't imagine that sleeping > > vs. alarm has any bearing though. Also, I forgot to mention that > > when the phone's screen turns off, my background service suspends > > itself (via Thread.sleep(99999999999999)) until the screen is turned > > back on, in which case the sleep get's interrupted and the thread > > continues. The net result is that the thread is only running (and > > consuming power, I'm assuming) when the screen is active. > > > I'm going to take Dianne's advice and do a more aggresive battery > > drain test, but if that turns out to not jive with the "usage meter", > > I think that I have chalk this one up to a really bad software > > approximation. > > > On Oct 8, 1:40 pm, RichardC <[email protected]> wrote: > >> By running your background task every 2secs your are basically keeping > >> the phone permanently on. Even though your app is not using much CPU > >> it has to wake the phone from any sleep state every 2secs. So it > >> either will not allow the phone to sleep or mostly keep it awake. > >> Waking the phone will power up all hardware devices that are needed > >> from any low power state they are currently in and reset their sleep > >> timeouts. > > >> Basically any background tasks (something not associated with the > >> current foreground activity the user is interacting with) should only > >> wake up very infrequently (say greater then 60mins). > > >> Also are you sleeping in your background task or using an alarm > >> event. Sleeping is bad ... see lots of posts by Dianne Hackborn on > >> this very subject. > > >> -- > >> RichardC > > >> On Oct 8, 5:55 pm, dadical <[email protected]> wrote: > > >> > I have an application that runs a background service. This background > >> > service wakes and runs once every 2 seconds. The background service > >> > registers as a listener with the orientation sensor with the lowest > >> > possible rate of event delivery (application). When my service thread > >> > wakes it uses the latest value delivered by the sensor events, so > >> > there is no heavy-weight processing being done on the sensor thread. > >> > Furthermore, the background thread is doing very light processing when > >> > it wakes. > > >> > I've done tests that show that my background thread poses very minor > >> > power overhead, somewhere around 3%. The test was basically: charge > >> > to 100%, leave phone on for two hours with service running, record > >> > battery level. Repeat with service off and compare. > > >> > However "Battery Usage" of my application is listed as some insanely > >> > high value (e.g., 40%). Over the same two hour period of the test, > >> > CPU usage was less than 3 seconds. > > >> > What does "battery usage" mean? In my case, it clearly isn't an > >> > indication of "battery drain", but that is what the stat seems to > >> > imply.- Hide quoted text - > > >> - Show quoted text - > > -- > Romain Guy > Android framework engineer > [email protected] > > Note: please don't send private questions to me, as I don't have time > to provide private support. All such questions should be posted on > public forums, where I and others can see and answer them- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
