NlpWakeLock and NlpCollectorWakeLock Discussion
Firstly, this is not another thread to complain about your horrible battery life due to Google Play Services. I'm tired of those (mostly on Reddit, but some here too. Either way, none of that here
). This is instead to try and find a root cause for it. "It's Google's fault" is not good enough for me, and if you truly care about your battery life it shouldn't be for you either. If all you're after is an easy way out to get your battery life back, then this thread is not for you. We're here to reach a solution where you can get location services and good battery life. I've done if before, on my Galaxy Nexus on 4.3, but it seems that something is wrong in KitKat. Let this be a place where we all dig deeper into this issue, perform tests, gather results, and then share and discuss them. Here's what I've got so far:
The wakelocks that cause this battery drain are NlpWakeLock and NlpCollectorWakeLock. Nlp stands for network location provider. As you may know, Android provides developers with two ways of gathering location information. One is through the GPS_PROVIDER, which uses the GPS, and the other is through NETWORK_PROVIDER, which uses cell towers and WiFi APs to get your position. According to their developer website , NETWORK_PROVIDER uses less battery, is faster, but is less accurate. GPS uses more battery, takes longer, but is good if you want an accurate location. I'm assuming this particular wakelock uses NETWORK_PROVIDER.
I also did some digging using ROM Toolbox Pro's autostart manager. My guess was that Google Play Services must be triggered every time a certain intent is broadcasted, since nothing obvious is telling it to run. Turns out there are quite a few. 30, to be exact. However, many of them have to do with GCM and we don't really care about those. One of particular interest is one called com.google.android.location.internal.NlpNetworkPro viderSettingsUpdateReceiver. It listens for the intent android.location.PROVIDERS_CHANGED. The LocationManager API's documentation tells us this:
Broadcast intent action when the configured location providers change. For use with isProviderEnabled(String). If you're interacting with the LOCATION_MODE API, use MODE_CHANGED_ACTION instead.
I'd assume that this means when you change your location providers, such as enabling/disabling data, WiFi, GPS, etc.
However, location reporting only seems to use network location. If you're on KitKat, go to the location settings and choose device only. Then choose battery saving. It asks you to accept location reporting. Same thing when you choose high accuracy. What do both of those have in common? Network location. You can switch between those two as much as you want and it won't ask you to accept again. However, once you switch to device only and back it will ask you. This shows that it only uses network location.
I find that Google (Play) Services has 5% (+/- 1%) keep awake. Tested on both Nexus 5 running KRT16M and Galaxy Nexus running JWR66V. Both use a certain time of GPS, although that number is never increasing. I assume this is some sort of initial one-time lock. It can be disregarded.
One more thing I noticed is that this Google Play Services issue is much more prominent on KitKat. While they have happened before, often times a simple Play Store update would fix it. This time it seems to be location based. Guess what changed in KitKat? The way you deal with location settings. It may be that the way location settings are grouped in KitKat cause that intent to keep firing, and that in turn triggers something that eventually ends up being what you see as NlpWakeLock.
What I'm going to try next is disabling that intent receiver and then monitor that wakelock as well as if location reporting still works. Feel free to play around, and be sure to share your results.
To those who are suffering from these wakelocks, could you please share your settings? Such as what type of location mode you have (high accuracy, battery saving, device only), WiFi on or off, data on or off, signal strength, WiFi always scanning, Play Store and Play Services version, what device you have, Android build number, and what ROM/kernel you're using if you are using one? Any other info such as screenshots of battery screen, betterbatterystats, wakelock detectors, etc. will all be welcomed.
Here is the Reddit thread I created discussing the same issue: http://www.reddit.com/r/Android/comm...ck_discussion/