Debugging Android Performance & Battery Issues--Like a Developer

I have a frustrating relationship with my phone's performance. I can cleanup my phone for a few days, but it tends to revert to being sluggish within no time. I've had dozens of devices and they all suffer from this.

There's a lot of voodoo about Android Performance and Battery life--task managers, factory resets, etc.

Here's a more developer-oriented process using adb .

Using ADB to identify process hogs

By connecting your device to the Android SDK, you can use ADB to identify process hogs. If you can, just remove the app. Otherwise, delete it's data (see pm clear below)

$ adb shell dumpsys cpuinfo
Load: 4.09 / 4.35 / 4.47
CPU usage from 17646ms to 1166ms ago with 99% awake:
  6.1% 211690/com.android.settings: 4.3% user + 1.8% kernel / faults: 1341 minor
  2.6% 294/surfaceflinger: 1.2% user + 1.3% kernel / faults: 38 minor
...

In this case the system settings app is using 6.1% cpu when the phone is idle. The workaround is to delete the app's data

$ adb shell pm clear com.android.settings
Success

This is a trial-and-error process. But the results are both noticeable and measurable--a snappier UI, fewer background apps and a longer battery.