[Samsung Epic 4G Touch] Capp5050:
A methodology for the frustrated...

I have a sense that there are many issues overlapping each other and causing confusion and lack of consistency. For example, like someone above, I had massive battery loss overnight one night. I checked the wakelocks and it seemed that the wi-fi was keeping the phone from entering deep sleep. I turned it off, and voila', my avg drain went from 250ma down to <80ma. Wi-fi then, right? Wrong. I re-connected to wi-fi the next night to confirm, and got low drain. So it was definitely the wi-fi on the first night, but that couldn't be the ONLY contributor.

When I was getting lots of LOS, battery drain would be high and AOS usage was high - perhaps the phone was trying to find a signal, even though the radio was 'off' and that drained the battery? who knows.

I've been monitoring the phone closely, (running Starburst 1.95 and LOStKernel 1.0.2.3), and I find NOW, after MANY tweaks, it USUALLY runs 'OK' battery. I define 'OK' as ~15-20 hours with normal use; some folks get 30+, some get 6-10 (horrible, and what I got originally) and making corrections along the way.

I''ll share my methodology. But because I'm not convinced that any of these 'fixes' address the underlying causes, I can't guarantee you they will work for you, or how long they'll last (I've had to repeat some), but you'll hopefully gain SOME gratification if you can squeeze more life out of your battery. Also, there are more thorough diagnostic methods available than I will present here, you can find them under the 'AOS bug' thread. Also, I will assume that the cause of your battery issues is not otherwise easily identifiable by e.g., going to 'Battery Usage' stats and observing an errant app running.

First : I would recommend a rooted phone, with the Starburst ROM installed (1.95 just came out, but if you're reading this within a few days of the 2011/10/31, you should probably install 1.9 to avoid some early install bugs). 1.9 also includes the LOSt Kernel. If you don't want to wipe your phone to replace your ROM, at the very least instal Chris41g's LOSt Kernel (I'm using 1.0.2.3 Stable version; avoid the Experimentals for now, because you don't want any uncontrolled variables). LOSt Kernel cuts the LOS's

significantly

and I am convinced this helps with battery usage (and eliminates another variable). And guys, if this DOES help you with your LOS, please make a donation to Phantom Hacker and Chris41g - these guys are doing Samsung/Sprint's work for them.

Second: You will need some apps. The pro versions (where applicable) probably add up to less than $20 - so buy them. They are:

- Battery Monitor Widget Pro (BMWP)

- Better Battery Stats (BBS)

- CPU Spy (CPUS)

- OS Monitor (OSM)

- System Tuner Pro (STP) (Optional)

Third: Methodology

- BMWP- Determine your consumption rate - If you have a Epic 4G Touch, and it has an 1800 maH battery, you theoretically will get 18 hours of usage if the phone drains at an average of 100ma per hour or less. Let's use this as our reference point. Use Battery Monitor Widget Pro. Download some of the free notification packs, specifically the 'maH' ones. Set the 'history update frequency' to 3 or 4 minutes, and the maH update rate to 60 seconds. Activate the the Notification area monitor for maH.

- Open BBS; create a 'custom reference point'; don't 'back' out of this app, use the Home key.

- Open CPU spy. Reset the data. close.

- Make sure your miscellaneous foreground apps are closed, and then turn off the screen and wait 15-20 mins. Leave the phone alone. Go watch the Walking Dead or something, but don't mess w/the phone.

- After 20 mins, wake your phone up again.

- Look at the current level widget in the notification area. If everything's ok, it should be reading about 70maH or less. If you've got crappy battery life, there's a good chance it's not. Also, remember, that while you ARE USING your phone, playing games, etc., the usage could run anywhere from 100maH to 400 or even 500. We're testing f4or usage during 'inactive' states, which is where most people's unexpected drain comes from.

- Assuming your drawing more current than you should be, you now head down the road of diagnostics and deductive reasoning. Because I've found so many different ways the device could go awry, instead of sharing MY findings, I'll simply summarize how each of the other tools I listed might be able to help you with your diagnosis.

- CPU Spy - Open CPU spy; hit 'Refresh Data'. If you did a 20 minute test, at least 15-17 of those minutes should show the processor in 'Deep Sleep' mode. If you're showing ZERO Deep Sleep, then your onto at least one cause - some app/process/service is preventing your phone from sleeping.

- Check out the history file in BMWP. Do the ma measurements show a steady decline to double digit #s (<100)? or do they stay high? If they stay high, there's an app/service running that probably shouldn't be.

- Open BBS; choose 'Since Custom Time' (which was about 20 mins ago), and then check what processes and more importantly, wakelocks were running. High # of wakelocks (sometimes) indicates an issue, especially if those wakelocks add up to a lot of CPU time (also indicated in the stats). Investigate any app that looks suspicious here.

- If you can't see any obvious app gone awry, go into OS Monitor; select to sort by 'Total Time' and make sure Kernel/OS is selected, so that you can see system processes as well. Look for a process hogging CPU time that has no reason to be. Android OS may be one of them. When it is, I will typically click on 'Android OS' and then at the prompt, click 'Show Logs'. There are tons of entries, but if you filter for 'Errors' you my find some unusual activity coming from one of your processes. FOR EXAMPLE: once I found hundreds of entries related to my media library on my SD card. I re-formatted the card, re-copied the songs onto it, the errors went away, and the AOS process dropped significantly.

- System Tuner Pro can also be used to monitor errant processes and services, but it also has the advantage of a) being able to record over a period of time, but more importantly b) being able to freeze a process. You don't want to go killing (many will re-start) or deleting, because you don't know where dependencies exist. But 'freezing' is a fairly benign way to see if a process is messing you up.

These aren't the most comprehensive of instructions, but hopefully give something to do for those of you who are frustrated and feel helpless. I knew none of this before scouring through this website, so if you find an issue or have a question about any of these products or methodologies, you should probably do a little more research on the site (the AOS Issue thread is invaluable).

Hope this helps.