1.. SPDX-License-Identifier: GPL-2.0
2
3=====
4BTRFS
5=====
6
7Btrfs is a copy on write filesystem for Linux aimed at implementing advanced
8features while focusing on fault tolerance, repair and easy administration.
9Jointly developed by several companies, licensed under the GPL and open for
10contribution from anyone.
11
12The main Btrfs features include:
13
14    * Extent based file storage (2^64 max file size)
15    * Space efficient packing of small files
16    * Space efficient indexed directories
17    * Dynamic inode allocation
18    * Writable snapshots
19    * Subvolumes (separate internal filesystem roots)
20    * Object level mirroring and striping
21    * Checksums on data and metadata (multiple algorithms available)
22    * Compression (multiple algorithms available)
23    * Reflink, deduplication
24    * Scrub (on-line checksum verification)
25    * Hierarchical quota groups (subvolume and snapshot support)
26    * Integrated multiple device support, with several raid algorithms
27    * Offline filesystem check
28    * Efficient incremental backup and FS mirroring (send/receive)
29    * Trim/discard
30    * Online filesystem defragmentation
31    * Swapfile support
32    * Zoned mode
33    * Read/write metadata verification
34    * Online resize (shrink, grow)
35
36For more information please refer to the documentation site or wiki
37
38  https://btrfs.readthedocs.io
39
40  https://btrfs.wiki.kernel.org
41
42that maintains information about administration tasks, frequently asked
43questions, use cases, mount options, comprehensible changelogs, features,
44manual pages, source code repositories, contacts etc.
45