(mis)adventures in software development...

17 March 2015

Laggy Lollipop: How to clear the cache partition on an Android Nexus 7

Category Android

Has your Nexus 7 become a horribly slow and sluggish mess after the Android 5 Lollipop update? Here's something that might help.

I usually approach any software update with a sense of mixed feeling. Especially operating system updates. The promise of new features or better performance is offset by the trepidation that the new version might be substantially worse than what came before. (Yes, I’m looking at you Windows 8!)

My fears were realised when my Nexus 7 tablet, which had been happily running KitKat, received the Android 5.0 “Lollipop” update.

Things were definitely not right after that. My Nexus became slow. Really, incredibly slow and sluggish and laggy. With frequent ANR dialogs.

After the Lollipop update, my Nexus 7 was so sluggish it was close to unusable. After some googling it was clear I wasn’t the only one experiencing this problem.

I tried clearing the cache partition, and found that this helped improve performance somewhat. My Nexus is still performing much worse under Lollipop, but it has at least gone from “unusable” to “barely usable”.

The steps to do this are as follows.

How to wipe the cache partition

Start with the tablet turned off.

  • Press and hold the volume down and power buttons until a screen appears with a large arrow at the top (kind of pointing towards the power button at the top right corner of the device).
  • Press the volume down button a few times until an arrow with “Recovery” appears.
  • Press the power button to select Recovery Mode.

An Android logo with an exclamation mark should now appear (with “no command” text).

  • Hold down the power button, press and release volume up once, then release power.

You should now see a text based screen with a list of options.

  • Use the volume down button to move the selection to the “wipe cache partition” option. Double check to make sure you have selected “erase or wipe cache partition”. DO NOT select “wipe data/factory reset” by mistake!
  • Press the power button once to select the “wipe cache” option.

The process of clearing the cache should now begin, and will probably take a few seconds. Once it’s done, you should be back at the same menu.

  • If necessary use the volume buttons to highlight the “reboot system now” option.
  • Press the power button to reboot your device.

Once your Nexus finishes rebooting, it should hopefully be at least a little more responsive and usable. Whether the improvement lasts remains to be seen.