New answers tagged processes
It's understandable that your battery life will decrease when you run 4.4 on an older device like the S2. But that is strange. Try identifying the process like the other users suggested. I would also suggest Greenify, an app that can put processes and apps into automatic hibernation, decreasing their CPU toll.
If you are rooted, I would recommend downloading Better Battery Stats (or Wakelock Detector) from the Google Play Store, and finding the name of the 'mad' processes. If you aren't rooted, I recommend you root as other apps can't access battery stats as of Android OS version 4.4.
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