Btrfs is a new copy on write filesystem for Linux aimed at implementing advanced features while focusing on fault tolerance, easy administration and repair. Initially developed by Oracle, Btrfs is licensed under the GPL and open for contribution from anyone.
Linux has a wealth of filesystems to choose from, but we are facing a number of challenges with scaling to the large storage subsystems that are becoming common in today's data centers. Filesystems need to scale in their ability to address and manage large storage, and also in their ability to detect, repair and tolerate errors in the data stored on disk.
Here are some key features of "Btrfs":
· Extent based file storage (2^64 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)
· Strong integration with device mapper for multiple device support
· Online filesystem check
· Very fast offline filesystem check
· Efficient incremental backup and FS mirroring
What's New in This Release: [ read full changelog ]
· v0.18 has the same disk format as 0.17, but a bug was found in the ioctl interface shared between 32 bit and 64 bit programs. This was fixed by changing the ioctl interface. Anyone using 2.6.29-rc2 will need to update to v0.18 of the btrfs progs.
· There is no need to reformat though, the disk format is still compatible.