Btrfs

Btrfs' (B-tree file system) is a new copy on write filesystem for Linux aimed at implementing advanced features while focusing on fault tolerance, repair and easy administration. Initially developed by Oracle, Btrfs is licensed under the GPL and open for contribution from anyone.

= Features = The main Btrfs features include:
 * Extent based file storage (264 max file size)
 * Space efficient packing of small files
 * Space efficient indexed directories
 * Dynamic inode allocation
 * Writable snapshots
 * Subvolumes (separate internal filesystem roots)
 * Object level mirroring and striping
 * Checksums on data and metadata (multiple algorithms available)
 * Compression
 * Integrated multiple device support, with several raid algorithms
 * Online filesystem check
 * Very fast offline filesystem check
 * Efficient incremental backup and FS mirroring
 * Online filesystem defragmentation

= See also =
 * Ext3
 * XFS
 * JFS
 * ReiserFS
 * Btrfs wiki
 * Btrfs at wikipedia