Ext3, the default Linux file system for many years, is definitely starting to show its age. Modern mass storage devices are approaching its limits and block-based data management is no longer adequate for modern file sizes. High time for an update!
The result of three years of Ext4 development has been significant advances from Ext3 which increase the volume limit to 1024 PB. This should be sufficient for many years to come. Extents, long implemented in other file systems such as XFS, should improve the efficiency of managing large files. There are also a whole range of under-the-bonnet changes intended to improve Ext4 performance compared to Ext3.
The kernel development team adopted the Ext4 code in version 2.6.19 to give it the opportunity to come to maturity in the kernel. Ext4 was marked as experimental in versions up to and including 2.6.27, but since Linux 2.6.28 the new file system is now considered stable. Not that this rules out the odd bug or other unpleasant surprise. The latest Ubuntu 9.04 can already be installed on Ext4 and the forthcoming Fedora 11 release will use Ext4 as its default file system.
I'm running ext4 with kubuntu 9.04, is fast and stable for me. cant wait for future releases with better SSD support and also hoping i can afford to buy one of these juicy SSDs next year..
