Btrfs is a new copy on write filesystem for Linux aimed at implementing advanced features while focusing on fault tolerance, repair and easy administration. . This package contains utilities (mkfs, fsck, btrfsctl) used to work with btrfs and an utility (btrfs-convert) to make a btrfs filesystem from an ext3. . WARNING: Btrfs is under heavy development, and is not suitable for any uses other than benchmarking and review.