OK, it's been 3 days, 18 hours and change, or 90 continuous hours. 90 hours! That's outstanding! Even more so because it's on my slightly less capacious Sprint battery, not the Japan-made (high quality) Samsung brand battery that came with the phone. My backup battery that I use for the frequent battery-killing charge/discharge cycles and keep my Samsung battery at full force for times when I need every last minute. I'm not going to discharge even that one past 20%, although I have no doubt that it could get into its fifth day if I pushed it. (Lithium secondary chemistry doesn't do well with deep discharge, so draining it to zero as a quick way to turn a 90 hour+ battery into a 9 hour battery.)
Here are some things to ponder:
1. The phone and battery are only a couple months old.
2. I've kept the phone dead stock, installing only applications (not utilities or replacement OS components other than a user mode antivirus program).
3. I used the stock Samsung-made ICS zip file to do the upgrade.
4. After the upgrade, I found a lot of settings that affect battery life altered, and some new features like "Power saving mode". I reset all of them to more or less the way I had it set up before. I set the new Power saving mode to kick in at the most aggressive 50%, assuming that the last 50% would be a lot shorter than the first. (Turns out it wasn't.)
5. I installed the test battery after a full charge, using the included Sprint charger.
6. Swapping batteries caused a temporary power outage in the phone, causing it to reboot. I'm told this is called a hard reset. Although I gave ICS 12+ hours to finish any background processes before the reboot, I did notice a lot fewer system processes after the hard reset. I didn't kill any of them so as not to bias the test.
7. I spent an hour or two going through the phone and verifying that it was still set up the same as it was before the reboot, and took one unexpected phone call, but didn't make any calls or use the phone to do more than check the battery state, so as not to bias the test results. No software updates were done during that time. I did clear messages, not knowing whether it cost more power to keep the reminder active. I did keep the Wi-Fi radio on during the test. The 4G (WiMAX), Bluetooth and GPS radios were kept off.
Why did I not use the phone? Isn't that abnormal? The obvious answer in this case is that the problems being reported from those fresh off their ICE upgrades was that ICS (and only ICS) was sucking up battery power at an unacceptable rate. Since PCS phones vary their output power automatically, there's no simple way to calculate how much energy a call would consume. Likewise, since the display was set to auto mode, which varied the brightness in response to the ambient light levels, I kept it off most of the time so as not to bias test results. Using the phone has no bearing on whether or not ICS by itself was draining the battery.
My conclusion is that those who experienced what they believed to be a battery-hungry ICS distro is more likely to be a battery-hungry ICS new user. Other possible factors include:
1.) Failure to reset the user settings. I noticed from the comments than many users assumed that ICS was the problem, and tried rash remedies like clearing all personal information off the phone. But I didn't read a thing (that I didn't write myself) about the easy to access (and I thought obvious) "Settings" menu. This may be a case of "new toy syndrome" and a rush to judgment by users who hadn't considered every possibility.
2.) New User Syndrome. We all want to check out the new install, so it only follows that we'd be using prodigious amounts of power in doing so. And those who are immersed in discovering all they can about the new attraction are less likely to pay attention to the difference between the way they're using the phone at the time and how they normally use it. It could be that simple.
3.) Background install processes. IME with embedded operating systems, it's not uncommon for the embedded hardware to be "just enough" to do its designed task, with little headroom. That makes it necessary for the OS to cope with CPU and RAM-intensive tasks like decompressing, organizing, configuring and installing new files by using every available shred of system resources that aren't needed for normal operation to perform these tasks in the background.
For example, the TiVo daily Program guide update takes anywhere from a few minutes to an hour to finish as seen through the graphical user interface (GUI) on the TV screen. However because the TiVo runs the Linux kernel and filesystem for the system, it's possible to use another user interface that's created by a well-known TiVo hack: the BASH shell and the GNU utilities. I've used these tools to monitor the runnung processes and CPU / RAM usage and can say with certainty that the daily update doesn't end when the GUI update display ends. It can take hours for the rest of the process to complete. GUI-only users can see this too if they watch the To Do List. They'll see new scheduled programs appear from time to time as they're added to the database. Other DVRs act this way too.
Another thing that could be happening is an exhaustive recalibration of the hardware by the new OS software. There have been quite a few reports of poor radio performance right after the ICS upgrade. For me these have settled down in a reasonable amount of time. If anyone is still having radio problems, please speak up.
4.) Unfamiliarity with the new user interface. Those who are experienced with the old version of Android might be misinterpreting what the new version is telling them. For example, the "(time) on battery" counter might be seen as a "battery time remaining" display. That's what I thought at first!
5.) The hardware. The new install and the reduced battery life could be a coincidence. Rechargeable batteries don't last forever, and it's possible that the big install was the last straw for an already exhausted battery.
DISCLAMER: This is only my best guess, and should be considered an opinion. The testing that I did wasn't rigorous or scientific, and all of the data at this time should be considered preliminary. Time will tell how things work out. If Samsung releases a new version of ICS, that would indicate that there are problems with this first release. Likewise, if the complaints stop coming, that will be telling too. My only interest is to figure this out, and have no intention to impugn the experiences of others, their good word or to insult anyone for any reason. Please accept this report for what it is and no more. Thanks!
Got any thoughts on that?
