[Vibrant Q&A, Help & Troubleshooting] XDAcat62:
Hi, I've had quite a few roms on the Vibrant (all JB) and they've all suffered from poor battery life due to a GPS wakelock getting out of control and leaving the phone stuck at 100mhz, unable to go into deep sleep. The wakelock I see mostly is ste-gps-interface. There isn't much out there except a previous post that I made thinking I fixed it (which wasn't the case, I just did something to make it happen more frequently). Interestingly enough too if you google "ste-gps-interface" nearly all the information out there is for the Vibrant. I know there have been GPS issues with this phone and I guess I'm lucky that GPS works at all.

Basically what would happen is that once the wakelock got started, nothing short of a reboot would clear it, and then it would happen maybe only a few hours after rebooting the phone again. Actually turning GPS off is not a solution. I think I even tried to kill the GPS daemon and that was not a solution either. Installing tweaking scripts seemed to trigger it more for me but I couldn't pinpoint any one action - it would just be the case that the longer I had the phone on, with any rom, inevitably the wakelock issue would rear its ugly head. I'm surprised not more people have mentioned it on here, but it could be that they're not aware of it, and just assuming that battery life is a little bad. It's acceptable when idling at 100mhz but I'd never get a full day out of it. I'm about one day and 4 hours now and at 40% with this fix. I have gone about 4 days with this fix and it seems to be holding so I'm fairly confident to say that at least for me it seems to have solved the problem.

Here is what I did. Download the app Greenify. This hibernates apps and services when the screen goes off. Curious to see if this would help my issues, I greenified Maps. This seemed to help a little bit, but the issue popped up again. I then turned Google Now into a user app via Titanium Backup and Greenfied that as well (Greenify won't let you freeze system apps, and it's safe to make google now a user app because it's not an essential process). You can find this app on the market. I have gone over a day today and I have only had 10 mins of the wakelock, opposed to nearly continuous (hours upon hours) of the wakelock, draining the battery. The only drawback I could see is if you depend on services that need maps or google now to be running when the phone is off, like latitude or location history. I imagine too that hibernating this nasty service just helps with battery life in general.

I'm very curious about this fix, because I wonder if it's a bug on Google's end. I've often thought that the location services seem buggy and excessive. This is worth trying just for battery alone. You can verify if you have the wakelock issue by using BetterBatteryStats and looking at kernel wakelocks (will have a ste-gps-interface wakelock going for almost the entire boot time), or even just looking at any CPU state breakdown - if you see only a tiny bit of time in deep sleep and the rest in 100mhz, that could indicate you're experiencing it as well. Please let me know if this helps anyone and thank you to the app developer of Greenify :)