EXT4, Btrfs, NILFS2 Performance Benchmarks Written by Michael Larabel in Software on 29 June 2009 at 02:00 AM EDT. Page 1 of 7. 38 Comments. The past few Linux kernel releases have brought a number of new file-systems to the Linux world, such as with EXT4 having been stabilized in the Linux 2.6.28 kernel, Btrfs being merged into Linux 2.6.29, and most recently the NILFS2 file-system premiering wit