2 replies to this topic

[MillyBays]

The Problem

If I can't find a way to fix this, I'll probably have to switch to another device.
My battery life on CM7 is awful. For example, if my battery is at 90%, and I do some light internet browsing/forum reading for 15 minutes, my battery will be down to about 80% by the end of those 15 minutes. It seems like the battery is always draining this fast whenever I'm doing something that requires data. But that doesn't make sense because I already tweaked the settings to conserve battery.

Things I have done so far
(Keep in mind, all of the following has been done already and has not fixed the battery life issue)
I'm on a fresh install of CM7 after a full wipe/factory reset, like you're supposed to. I usually am connected to 3G only.
Wifi Sleep is set to Never. (Settings > Wireless & Networks > Wi-Fi Settings > Advanced)
End Button Behavior is set to Go To Sleep. (Spare Parts)
Background Data and Auto-sync is disabled. (Settings > Accounts & sync)
Google Latitude/Google Maps is not installed.
Use GPS satellites and Use wireless networks in Location & security settings are disabled. (Settings > Location & Security)
Brightness is set to auto.
CPU is throttled to 768max on the conservative governor, with 384mhz max while screen is off.
Use Dalvik Just-In-Time compiler is disabled. (Settings > Cyanogenmod settings > Performance)
Enable surface dithering is disabled. (Settings > Cyanogenmod settings > Performance)
I wiped the dalvik-cache in recovery.
I wiped the /cache/ partition in recovery.
Pretty sure I don't have a rogue app, I barely have any market apps installed in the first place.
Haptic feedback is disabled.
I have a spare battery, I've been using the same battery for about a year now.

My device reports that display is using 45% battery, 38% for cell standby, 8% for phone idle, 2% for Android OS.

Here is a screenshot of the battery usage graph:
http://i.imgur.com/obhE7.png

When viewing a logcat, this gets spammed repeatedly:
"D/dalvikvm( 2230): GC_EXTERNAL_ALLOC freed 41k, 49% free
2970K/5767K, external 1738K/1805K, paused 32ms"
there are some changes in the numbers there, though, such as the % free, and the amount freed. But it still spams and fills up the whole screen repeatedly. Not sure if that's normal or not.

So, does anybody know of a way I can fix my horrible battery life? I'm on the verge of having to get a new device, especially if this continues.
All help is greatly appreciated, and I'll be happy to give you any information you need ASAP.

Thanks.

[samarium]

Down 30% after 7 hours doesn't look too bad.  If you get more than a day from the phone and actually use it, rather than just leave it in your pocket, then you are doing well.

Turning of the Dalvik JIT compiler is probably counter productive, as this would mean the code has to be reinterpreted all the time.

logcat GC_EXTERNAL_ALLOC is just the garbage collector going around an freeing memory, this is normal.  If y you don't want to see it, then there might be some options to logcat to disable display of these messages.

screen will use battery if it is on, that is going to happen and is the major user of my battery.  I find auto brightness is often too bright, and sometimes just set to 25%.

Probably the first thing I'd do is download the "Battery Calibrator" app from market, so you can see what your battery capacity is, although if you aren't seeing phone powering down with apparently > 5% battery left, then calibration is probably not a major issue.  The is a thread on XDA.  Using battery calibrator you can reduce the empty point of the battery to get a bit more capacity from it,

Do you have good cell reception?  If not the cell radio can repeatedly be both hunting for good reception on either 2G or 3G bands, or swapping between them if you have data enabled and 3G is noticably worse than 2G.  IIRC Tmobile has some issues like this.  Go to the dialer and dial *#*#INFO#*#* and you will be able to set which cell radio modes you want, or you might be able to do the same with the notification power widget or the power control widget or any number of apps.  If I was trying to reduce drain, and data was off or slow was ok, then I would lock down the GSM ie 2G only.  Your battery picture shows EDGE, which I think is 2.5G, not HSPA, which is 3G, so if your phone is constantly hunting for 3G connectivity while only getting EDGE, it would be burning power.

Are you seeing the same battery drain in flight mode? Wifi only? 2G only? 3G only?

The antennas app can be useful for seeing where the cell towers are and which one you are using etc.

Seems like you have plenty of scope for further investigation.

Seems like

[MillyBays]

samarium, on 28 October 2011 - 11:54 PM, said:

Probably the first thing I'd do is download the "Battery Calibrator" app from market, so you can see what your battery capacity is, although if you aren't seeing phone powering down with apparently > 5% battery left, then calibration is probably not a major issue.  The is a thread on XDA.  Using battery calibrator you can reduce the empty point of the battery to get a bit more capacity from it

Going to try the battery calibrator. I assume you're talking about this one?
https://market.andro...alibratebattery

Also, I do have good cell reception in my area. I have it set to switch between 2G only and 3G only, most of the time I have it set to 2G.

Still haven't found the solution to this issue, I hope to soon.

EDIT: My radio is also outdated (4.06.00.12_7) I'll update it and see if that fixes anything. Does anybody know where I can find the latest N1 radio image?

Edited by MillyBays, 04 November 2011 - 12:09 AM.