Android File System Switching To Ext4 With Gingerbread

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I know this will appeal to a very minor percentage of our readers, but the Android operating system will be/has switched to a new file system with the new version, 2.3 “Gingerbread”. Previously, Android used the “YAFFS” file system. With the switch to Ext4, users will see increased performance with dual-core phones. This is a hot issue, considering that we’re expected to see dual-core phones coming in 2011.

YAFFS, or Yet Another Flash File System, (as mentioned) was the file system in Android previously. It’s only single threaded, meaning that you won’t get optimized read/write performance with dual core processors. As the folks at IntoMobile explained, you may wonder why you need good storage performance on a mobile phone, but with manufacturers starting to cram 11MP cameras and 720p video recording into these phones, you can see why it might be handy to have a quick file system. Plus, if we ever see a 64GB Android tablet (like the 64GB iPad), then you could fit all sorts of stuff on there.

Because ext4 does not dump data to persistent as quickly as ext3, developers must be mindful to write user data to persistent storage often. This reputation that ext4 ‘enjoys’ has given it somewhat of a negative reputation among some who believe that it frequently loses data in the event of a system crash. Google has gone on the offensive this front, with Google’s Tim Bray writing a piece on the developer’s blog, reminding developers to use a system call named fsync() that will help make sure that data is being written to persistent storage.

Google has actually been assisted on this front by a chap named Ted Ts’o who was at the forefront of Ext4 development. Ts’o was hired by Google to help them import their servers from Ext2 to Ext4, and while Ars Technica says he wasn’t involved in the Android team’s decision to move to Ext4 from YAFFS – he helped them on the route once the decision was made.

It’s good to see the Android team keeping the operating system up to date with all the latest developments in the Linux space (well, relatively).