For all its qualities, the original Nexus 7 had a problem – it got slower the longer you used it. At least that’s what many users reported in righteous outrage.
The problem was related to low-level software, specifically to the way information was written on the flash storage of the tablet. As long as the data blocks that make up the storage were empty (when the tablet was new), writing data was quick and the operating system ran smoothly. As the storage space filled up, the operating system kept looking for free data blocks to use, which was fine until all the blocks became used up. At that moment, the operating system had to delete blocks before writing them, which caused the tablet to slow down dramatically.
The solution is for the OS to periodically issue a TRIM command, which goes through every data block that is no longer in use and wipes it. This way, when data needs to be written on the flash storage, plenty of empty blocks are available.
TRIM doesn’t work on the Nexus 7 on Android 4.2, which explains why so many users have been having performance issues.
The good news is Android 4.3 supports the TRIM command, which means two things: the Nexus 7 (2013) won’t be having the same slowdown problems as the first generation, and the Nexus 7 (2012) should work better once you update it to Android 4.3.
According to Brian Klug of AnandTech, Android 4.3 will run the fstrim command daily, ensuring that wiped out space is constantly available on the Nexus 7. The command will run when the device is idle, the display turned off, and the battery is above 70 percent.
That means you shouldn’t expect to see an instant improvement as soon as you upgrade your Nexus 7 (2012) to Android 4.3. The trick is to leave the tablet a few hours unused and with the battery charged, so TRIM can work its magic.
The solution was available before to rooted Nexus 7 users through various apps, but it’s good to see Google working to improve the experience for everyone.