Recently when benchmarking the Btrfs and EXT4 file-systems we were left surprised that the performance of the next-generation Btrfs file-system had regressed against EXT4 to the point where the evolutionary file-system is measurably faster in a greater number of disk benchmarks.

This morning we published benchmarks of ZFS, EXT4, and Btrfs when running these three popular file-systems off a high-performance OCZ Vertex 2 solid-state drive. To a fair amount of surprise, the EXT4 file-system ended up beating out Btrfs on the SSD in a number of tests.

With the EXT4 file-system having been stabilized with the Linux 2.6.28 kernel, the Ubuntu developers are preparing to adopt this evolutionary Linux file-system update. EXT4 will not replace EXT3 as the default file-system until at least Ubuntu 9.10, but as of yesterday, Ubuntu 9.04 now has install-time support for EXT4.

The past few Linux kernel releases have brought a number of new file-systems to the Linux world. Being the benchmarking junkies that we are, we have set out to compare the file-system performance of EXT4, Btrfs, and NILFS2 under Ubuntu using the Linux 2.6.30 kernel.

Earlier this month we delivered benchmarks comparing the ZFS, EXT4, and Btrfs file-systems from both solid-state drives and hard drives. In this article we have our Btrfs test results when the zlib compression mount option was enabled for looking at the SSD compression performance.

File-system benchmarks have become quite common to Phoronix in the age of EXT4 and Btrfs with these new file-systems driving much of the interest and as we have also been finding the Linux file-system performance to change between kernel releases. This time around we are using a Git snapshot of the Linux 2.6.34 kernel.

To see how this changes the Linux file-system landscape, atop the latest Linux kernel we have a fresh set of benchmarks for EXT3, EXT4, XFS, ReiserFS, and Btrfs.

The default journaling file system on non-boot partitions on Ubuntu 11.04 is ext4. Other journaling file systems supported are ext3, xfs, jfs, reiserfs, and btrfs. The journaling file system of interest in this article is btrfs, the B-Tree File System. Btrfs is an ongoing attempt to create a ZFS-like file system for Linux.

ext3 and ext4 file systems can be converted to btrfs. For non-root file systems, this can be done online (i.e., without reboot), while for root file systems we need to boot into some kind of rescue system or Live CD. This guide explains how to convert an ext3 or ext4 root file system into btrfs on Ubuntu 12.10 and how to roll back to ext3/ext4 again if desired.