Suggestions for a Kernel that Will Help to Improve Battery Life the Most

[androidluvr2]

My battery life is so bad on Jelly Bean even with the extended battery. I don't use my phone all that much but I do keep the bluetooth, location services, Google Now and 4G LTE on all the time as well as sync and back-ups, which I would like to continue to do so I would like to install a custom kernel on the device in the hopes I could improve my battery life.

Any suggestions as to which I should try? I am running stock 4.2.2 with the 4.1.1 radios.

 

[blade22222]

You could try lean kernel or the kt kernel and if you don't like the battery life you can always customize it.

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[xderiwx]

Would using Lean Kernel or KT automatically improve battery life over stock kernels, or do they need to have the voltages tweaked to offer any noticeable difference?

 

[androidluvr2]

Would using Lean Kernel or KT automatically improve battery life over stock kernels, or do they need to have the voltages tweaked to offer any noticeable difference?

It might be best to start a separate thread to answer that. I don't know but I am interested in the answer, too.

 

[blade22222]

It depends on how it was installed. If it was included with a rom then it was probably adjusted by the developer. I think if it's installed as a stand alone it has generic setting and would need to be adjusted for your device/rom.

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[tayswg20]

My battery life is so bad on Jelly Bean even with the extended battery. I don't use my phone all that much but I do keep the bluetooth, location services, Google Now and 4G LTE on all the time as well as sync and back-ups, which I would like to continue to do so I would like to install a custom kernel on the device in the hopes I could improve my battery life.

Any suggestions as to which I should try? I am running stock 4.2.2 with the 4.1.1 radios.

I would suggest the KT kernel as well. When you flash the kernel it also installs the KTweaker app which controls all the functions of the kernel. Its pretty self explanatory and it comes undervolted a little even if you flash it as a stand alone install. What I always do first is 1.Open the KTweaker app and tap the "general" tab and check "enable OC Steps", the first time you do this you'll be prompted to allow supseruser. 2. While your still in the "general" tab, tap on the I/O Scheduler tab and switch it to sio. 3.while your still in the "general" tab, tap on the "CPU governor" and pick which one you want. I use ondemand but since you want better battery life, I would pick powersave, sleepy, or lazy. It might not be quite as smooth as ondemand but if battery matters to you then its worth it. 4. this should actually be number two but ......while your still in the "general" tab, you need to decide what you want your min and max frequencies to be. Since you want better battery life I would keep the max frequency at 1512. The default min frequency is 384 but I lower mine to 192 because my phone starts acting wonky if I set it any lower, this varies by phone so you'll just have to play with it a little. 5.While still in the "general" tab, you can adjust your "Touch Booster 1st" and "Touch Booster 2nd" I keep my "1st" set at the same as my max frequency which in your case would be 1512 and then keep my "2nd" at just a little lower than that. If you don't feel like messing with that setting, you can just leave it at the default setting, but I think it makes my phone respond quicker when i adjust it a little higher. 6.hit the back button to back out to the main menu and then hit the "voltages" tab. Like i said before, it already comes undervolted a little but I always lower mine even a little more. The quickest way to do this so you dont have to adjust each frequency one at a time is to just hit the menu button and it will give you the options to subtract or add in increments of 5 or 25. I usually lower all my voltages another 25 but some phones cant handle lower frequencies well, so i would suggest you lower it by five and see if your phone is ok then keep doing that untill you get to the desired voltage. In my opinion I wouldn't go much more than 25mv lower than what was the default voltage. Others may disagree but lowering to much can send you into a bootloop and you have to pull the battery and its always good to try and avoid all that. 7. After you've let your phone run for a day with your desired settings you can then optionally "set options on boot" if you want. If you want to do that then go to the main screen and hit the "set options on boot" tab and select your desired delay. I have mine set to 10 seconds so that if something goes wrong, I have time to open the app and stop it.

I leave all the other options like they were set as default because they work just fine for me, but if your brave and want to tweak things even more, the KTweaker app is pretty easy to navigate.

You can find the kernel on XDA under original android development.

Good luck

 

[scorpiodsu]

KT kernel is great. I an running that on the latest Jelly Beans build. I have the powersave governor set for when the screen goes off and the processor set to underclock to the minimum and running ktoonservative kernel when the device is awake and I get great battery life. Just as a comparison for you:

Stock kernel w/ Juice defender on aggressive and no other CPU tweaks, all location services off - Off charger by 8:30AM for work by noon with minimum use (couple texts, refresh RSS feeds and a couple emails when Juice defender let's it sync) my battery would be down to 60%

KT Kernel with the settings as above (except google services on) and NO juice defender - It's now 12:40PM and my battery is at 93% with the same usage. I'm getting all my emails on time and google location services are on and device feels just as snappy.

So being able to get those stats without having to shut off my connections is big. I don't use my phone at work much and data signal is iffy so I would suffer serious drain because of poor signal. On this ROM and kernal I am also getting stronger 4G signals where it was very weak on non existent. So combine stronger signal with the control over the CPU and I'm doing good. And it could be better if I change some of the other voltage settings or pick another governor. Haven't had time to play around with them yet. Get this ROM/Kernel combo!

The problem with the device is not that they use too much power but that they use too much power when we aren't using them and that's frustrating. So really limit the phone when screen is off works wonders and most governors adjust accordingly to your tasks and will ramp up speed when necessary. Over on SD they have some good threads that explain what each governor does in KT.

 

[scorpiodsu]

Wanted to show some battery stats. With the same use I could theoretically get nearly 24 hours and 4+ hours on screen time. Keep in mind I also streamed a couple Ncaa games for about 30 min as well.

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[androidluvr2]

is that the extended battery?

 

[scorpiodsu]

is that the extended battery?

Nope. Stock. It's all due to the ROM/Kernel and the settings. I would probably get even better battery life if I turned of Google services, turned off wifi when not in use, didn't stream anything (which doesn't happen often anyway) turned the brightness down some and tweaked some more of the CPU settings. But I'm good with this. I charge my phone every night so as long as I can make it to bed on a single charge, I'm good. I've been sitting at my desk at work for and hour and a half and only checked a couple emails and the battery is still at 100%.

 

[mammoth1010111]

Wanted to show some battery stats. With the same use I could theoretically get nearly 24 hours and 4+ hours on screen time. Keep in mind I also streamed a couple Ncaa games for about 30 min as well.

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That doesn't really count since you charged it what looks like 20-25% in the middle of the graph.

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