Notice: This post was first published in my old wordpress blog at http://zidsdreamyworld.wordpress.com, that blog now is replaced with this website, so i am moving the post here to this site.

Recently some guy at XDA found out why the old beast galaxy S2 battery drains so quick and gets very hot (near back camera) when running on custom OS. It is caused by some bug in kernel, even Samsung official kernels are affected with this bug called “fpbug” and that is the major cause of massive battery drain.

I’m glad some guy found out that error and released some kernels that are stable and currently working with cyanogenmod.  I flashed this kernel on my i9100 and the result was impressive!  The phone no more gets hot for no reason, battery backup is great (what you can expect from a custom OS). currently I’m using it with cm11 cyanogenmod snapshot M12

 

 

Here’s The Test Result :

– CPU Overheating near the camera fixed.

– Deep sleep battery drain fixed. Before when you go to sleep leaving phone on, it would have turned off by the time you wake up because it would be still causing unwanted load to the processor and draining battery.

Now imagine you have 100% charged battery and puts it on the table and you go to sleep, then you awake in morning and if you look the battery status there’s still 96 – 95% or more battery left! It was not possible before i flashing the kernel, in fact i would wake up and find my phone is dead. Now it’s fixed!

– It doesn’t get hot

– Battery lasts longer!

How to install it?

Make sure your phone is i9100, download cyanogenmod snapshot M12 ROM for i9100

Go to recovery,  do a wipe and clear cache,  then flash cm11 snapshot M12 i9100

And then flash the kernel that you downloaded. Make sure you download kernel- Lanchon-FPBug-20141218-cm-11-20141115-SNAPSHOT-M12-i9.zip

Then flash Gapps, if you want and then reboot!  Now your galaxy S2 can run a Marathon!. Download greenify and greenify all unwanted apps. go to Settings > performance   change CPU mhz to at least 1000 mhz or 800 mhz. These steps are done to get maximum power out of your battery,  Good luck with new kernel!

Kernel Download: select kernel that contains “fpbug”, if you choose other, it won’t work choose wisely, for the ROM you have

XDA Thread:  Here

Note:
These kernels are for cm (cyanogenmod)only, it may not work on other roms such as omni, resurrection and pacman etc, most likely, try at your own risk