1. Download our Official Android App: Forums for Android!

Root They Key to battery immortality?

Discussion in 'Android Devices' started by kanaida, Nov 9, 2011.

  1. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    I just noticed something that keeps bugging me.
    When I had my LG Optimus M, in the battery status I would always see "Display" as using the most battery, followed by cell standby, wifi, bluetooth and android system.

    On my LG Esteem I only see the following after tuning all kinds of stuff:

    Android System 96%
    Cell Standby 2%

    I've come to 2 possible conclusions.
    Either:
    a) something is different in the software that makes Android System use more cpu than it should. In this case if we find the root cause, our battery life could be ridiculous. Like 15 hours+ of normal usage. Currently I get about 10-11 normal usage.

    b) They are just simply hiding it for some reason. In this case we can find a way to enable this statistic and show our true usage to get accurate stats.

    I've left my display on for the entire duration of today until the battery went dead just to see if it would even appear and it has not. Let's try to get to the bottom of this.

    If anyone still has an Optimus m, please post your battery stats with usage % for comparison.
     

    Advertisement

  2. nuked

    nuked Well-Known Member
    Rank:
    None
    Points:
    43
    Posts:
    179
    Joined:
    Oct 9, 2011

    Oct 9, 2011
    179
    35
    43
    noticed the same thing, and tried looking for an app that would show better stats but came up with nothing. Maybe android system is all things lumped together, which is not very helpful battery stats at all.
     
  3. Prime85

    Prime85 Android Expert
    Rank:
    None
    Points:
    93
    Posts:
    800
    Joined:
    Feb 7, 2011

    Feb 7, 2011
    800
    201
    93
    Camera is listed under Android system which i think is strange. I took a video of an hour lecture today, i was wondering if it would have shwon up on the battery due to it being under Android system i have no idea how much it uses
     
  4. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    I'm testing out one possible fix for part of the problem.

    There's an app that polls the sensors for data a little too often, i'm testing injecting a delay to see if i can cut cpu from a constant 4-5% down to about 2%
     
  5. Prime85

    Prime85 Android Expert
    Rank:
    None
    Points:
    93
    Posts:
    800
    Joined:
    Feb 7, 2011

    Feb 7, 2011
    800
    201
    93

    If you figure this out are you going to add it to your app?
     
  6. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    Yes in my next update, and I will also share it with everyone here in good faith so we're all on the same page as I want to include the recovery image in my app as soon as it's available as well.

    So far i've charged up my phone and let it go down to 90% battery.
    I have good news, i see the following in battery status:

    Android System 96%
    Cell Standby 2%
    Display 2% <--- first time i've EVER seen this so it's on the right track for sure. :D

    Open a terminal
    type su
    cat 250 > /data/delay

    it will make a file called delay in the data folder with a value of 250 inside.
    The sensor polling service has a piece of code that reads that specific file and uses it to poll less often.
     
  7. ShinySide

    ShinySide Android Expert
    Rank:
    None
    Points:
    313
    Posts:
    5,504
    Joined:
    Jul 30, 2011

    Jul 30, 2011
    5,504
    2,680
    313
    Palm Bay, Florida
    I have all the same in the list except for display. I have Phone idle instead.

    Android System- 84%
    Cell Standby- 11%
    Phone Idle- 6%
     
  8. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    That's good. Idle is what we want to make it. :) I left my screen on for a good while tho.
    next step is switch to LG keyboard, Swipe is a nasty CPU robber. if you still want swipe try touchpad keyboard.
     
  9. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    So far it's looking like I might get an extra hour of continous use. I'm testing other values.

    This is what I know so far:
    -/system/bin/akmd2 is eating up the cpu
    -You should not attempt to remove or disable it, as its what reads all sensors such as gps, gravity, rotation etc...
    -It should not be running when the phone is locked, yet it does. (trying to figure out how to solve this one as it would bring large battery gains
    -/data/delay holds a value in milliseconds? and this controls how often it reads the sensor data. Higher values mean less responsive sensors but better battery, lower values make sensors report much faster/smoother but uses more cpu. I'm working on finding the perfect balance.
    -If you uninstall an app that appears on this battery stat list, it kind of skews what you see. So when testing, don't uninstall apps during that "unplugged" period.

    And guess what guys, I'm dead on. Not too shabby for a first guess :D Look at what a screen capture got right before it loaded the "Android System" icon and text that groups stuff together.
    [​IMG]
     
  10. nuttmeg

    nuttmeg Android Expert
    Rank:
    None
    Points:
    313
    Posts:
    7,331
    Joined:
    Feb 9, 2011

    Feb 9, 2011
    7,331
    2,526
    313
    Making you wonder?
    Lone Star State
    another thing is, if your phone is out of the service area, and it keeps looking for service that will also eat your battery up.
     
  11. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    That one sounds like it's by design, A phone radio needs to "stand by" in order to wait for calls. The lower the signal the higher the transmit power is needed to talk to radio towers. Other than putting it in airplane mode when you know you're gonna be in a far away area I'm not sure there's much that can be done, except maybe disabling the radio and turning it back on every couple minutes to check if we're in an area with service now. That might be a bit tricky to check but i'll see. It sounds like the kind of thing juice defender would do, but I did my own testing, and it doesn't seem to turn things like wifi off when it says it does on this particular phone. I experienced no extra battery gains when using it.
     
  12. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    This weak has been tested as working and added to my Lg Esteem Optimizer app.

    Note: It may sound tempting to use a sensor tester app, all of the ones that I tried seemed to keep chewing cpu after they were closed as if the program kept running in the background, just not displaying stuff. They all seemed to eat about %50 of the battery
     
  13. cheluz245

    cheluz245 Well-Known Member
    Rank:
    None
    Points:
    38
    Posts:
    141
    Joined:
    Mar 31, 2011

    Mar 31, 2011
    141
    10
    38
    Ninja
    Los Angeles
    I can only see Android system @ 97% and Cell standby @ 2%?
    Also, Whats the command you gave us for?
    When i type into Terminal Emu. I get "No such file or directory"
     
  14. Prime85

    Prime85 Android Expert
    Rank:
    None
    Points:
    93
    Posts:
    800
    Joined:
    Feb 7, 2011

    Feb 7, 2011
    800
    201
    93

    Same with mine
     
  15. cheluz245

    cheluz245 Well-Known Member
    Rank:
    None
    Points:
    38
    Posts:
    141
    Joined:
    Mar 31, 2011

    Mar 31, 2011
    141
    10
    38
    Ninja
    Los Angeles
    So we're on the same page.
    Did you type in the command into a terminal?
     
  16. kanaida

    kanaida Android Expert
    Thread Starter
    Rank:
    None
    Points:
    113
    Posts:
    788
    Joined:
    Dec 2, 2010

    Dec 2, 2010
    788
    336
    113
    .Net and Android Programmer
    Hey guys, instead of cat it was supposed to be echo, sorry

    echo 250 > /data/delay
     
Tags:

Share This Page

Loading...