Linux Foundation is organizing a end user collaboration summit this week. A major topic will be a presentation on the new upcoming filesystems – Ext4 and Btrfs. Ted Tso, who is a Linux kernel filesystem developer on a sabbatical from IBM working for Linux Foundation for a year, has talked about the two-pronged approach for the Linux kernel, taking a incremental approach with Ext4 while simultaneously working on the next generation filesystem called btrfs. Read more for details.
Ext4, a incremental revision of ext3 is built from the same codebase and compatible to it while providing better performance and scalability but there are limitations to what can be done in a compatible manner. Btrfs is now a multi-vendor effort from Red Hat, HP, IBM and Oracle allowing a common pool to save costs of development and will provide a number of additional features which requires a fundamental redesign.
These new features are expected to include storage pools, writeable recursive snapshots, fast file checking and recovery, easy large storage management, proactive error management, better security, large scalability and fast incremental backup. In reality most users don’t have databases large enough to require some of the most advanced functions but like so many technology battles, it comes down to bragging rights and engineering pride.
While Ext4 has long been merged into the Linux kernel as a development filesystem, it is getting closer to being marked as stable and beginning to see adoption from Linux distributions. Fedora 9 already includes ext4 as a technology preview and Fedora 10 will make it simpler for end users to adopt it as well although ext3 remains the default for Fedora and many major distributions.
Andrew Morton, a core Linux developer has indicated that he would like to get btrfs merged as early as 2.6.29 though it will be marked as a development or experimental feature for a while. This will allow btrfs to progress further as part of the Linux kernel development and will likely be the default for major distributions sometime in the future.