Get to Know Btrfs | Linux.com

https://www.linux.com/learn/tutorials/533112-weekend-project-get-to-know-btrfs

As expected, Storage Spaces will indeed be a feature of both desktop and server editions of the operating system.
If the feature does indeed ship in desktop Windows, it will overnight obsolete a range of SOHO-oriented storage systems; products like Drobo and ReadyNAS will find it hard to survive in a Windows 8 world.

Btrfs Features

• RAID 0, 1, 10
• COW
• Incremental backup
• Online defrag
• gzip and LZO compression
• Space-efficient packing of small files
• Dynamic inode allocation
• Checksums on data and metadata
• Shrink and grow storage volumes
• Extents
• Snapshots
• 16 EiB maximum file size

Planned features include RAID 5 and 6, deduplication, and a ready-for-primetime filesystem checker, btrfsck. You can try out btrfsck now because it is included in btrfsprogs. (Which of course Debian/Ubuntu/Mint etc. changes to btrfs-tools, and Fedora calls it btrfs-progs.) But it is not ready for production systems yet.
Putting the finishing touches on btrfsck is the last big step before Oracle makes it the default filesystem in their next Unbreakable Linux release. Fedora 16 Linux was supposed to default to Btrfs, but now they're aiming for Fedora 17 in May 2012.


also see https://btrfs.wiki.kernel.org/