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 is no longer in operation. 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.

Based on ext3, the ext4 file system is actively being developed.

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