Reiser4, btrfs, ext3 and ext4 Linux file systems news

Several new developments around the Reiser4, btrfs, ext2, ext3 and ext4 file systems, which are mostly used under Linux, have been published in the last few days. It appears that Namesys, the company behind the development of Reiserfs and Reiser4 and founded by Hans Reiser, who has been accused of murder, is no longer in operation. The company web page had sporadically not been available for weeks; now, even the DNS entry for namesys.com has disappeared. Namesys employee Edward Shishkin confirmed in an interview with CNet news service that the company's "commercial activities" had ceased

and that there was a problem with the web page.


However, he and several other developers would continue to develop the Reiser4 file system. The file system's source code is now available for download as a patch for Linux versions 2.6.22 and 2.6.23 on a web page maintained by Shishkin. Reiser4 also continues to be part of Andrew Morton's mm developer kernels and received several updates in the recently released version 2.6.24-rc8-mm1. Whether the file system will be integrated into the "official" kernel maintained by Linus Torvalds remains unclear even years after the introduction of Reiser4. Without a company or Linux distributor to guarantee its long-term development, chances for its integration remain slim.

Based on ext3, the ext4 file system is actively being developed. Kernel version 2.6.24, which is expected for release during the coming weekend, offers additional new features. "Uninitialized Block Groups" are to speed up the process of creating and checking ext4 file systems, while "Flexible Block Groups" speed up the processing of large files on file systems with small block sizes. Ext4 will maintain its experimental status. Apart from the ext4 improvements, two patches (1, 2) designed to speed up the checking of ext3 file systems in various ways are also being discussed by developers on the kernel mailing list.

The developers of btrfs, which has been redeveloped from scratch, have released version 0.10. It allows the size of btrfs file systems to be changed in runtime environments. An add-on serves for converting ext3 file systems to btrfs. Like ext4, btrfs is still being developed and should not be used in productive environments. With its new ideas, btrfs has already caused quite a stir in the Linux world; however, considerable work remains to be done according to developers until the file system is complete.
Source :http://www.heise.de