The Btrfs file system is designed to meet the expanding scalability requirements of large storage subsystems. Because the Btrfs file system uses B-trees in its implementation, its name is derived from the name of those data structures, although it's not a true acronym. A B-tree is a tree-like data structure that enables file systems and databases to efficiently access and update large blocks of data, irrespective of how large the tree grows.

The Btrfs file system provides the following important features:

• Snapshots: Btrfs uses Copy-On-Write (COW) functionality so that you can take near instant readable and writable snapshots. Snapshots can enable you to roll back a file system to a previous state, even after converting it from an ext3 or ext4 file system.

• Instant file copy: Similar to snapshots, you can use the reflink feature available in Btrfs to perform instant copies of large files on the file system.

• Logical Volume Management: Btrfs includes integrated logical volume management that feature built-in data redundancy, software RAID functionality, and the ability to dynamically add and remove storage capacity.
• Online maintenance: Btrfs includes features for online repair and maintenance operations, which minimizes downtime.
• Corruption detection and correction: Btrfs verifies checksums each time a data block is read from disk to help ensure data integrity.
• Compression and Defragmentation: Btrfs includes automatic and transparent defragmentation for improved performance. Also, Btrfs can apply compression to the file system, individual subvolumes, or to specific files and directories. Compression can provide significant disk space savings.
• Remote send and receive: Btrfs includes a send and receive function that can be used to efficiently perform remote incremental backups to save bandwidth and to easily create a remote mirror of a subvolume.

• File system seeding: Btrfs can be used to create a read-only file system that acts as a template to seed other Btrfs file systems, similar in functionality to other union mount file system types such as overlayfs or qcow2.

For more information, visit https://btrfs.readthedocs.io/.

For an overview of local file system management, see Oracle Linux 10: Performing File System Administration.