The new Android 4.3 Jelly Bean update that Google recently released alongside the new Nexus 7 device and which will also roll out to the Nexus 4, Nexus 10, Galaxy Nexus and the old Nexus 7. One thing that plagued the old Nexus 7 tablet is exactly the slow storage I/O performance that is thankfully fixed with the new update.

According to Anandtech.com, the new Android 4.3 update actually brought support for "fstrim", an application that TRIMs the blocks not used in the file system. Basically TRIM uses paging in order to tell the OS and flash memory controller that certain block is no longer in use.

According to Anandtech, you should be able to check if the "fstrim" is running over adb and simple "adb logcat -d | grep -i fstrim" command. Of course, the TRIM will be different on various devices due to different controllers.

The new Android 4.3 update will allow users who have been experiencing slow I/O performance will now see a decent performance improvement.

Source: Anandtech.com.