| Developer(s) | Matthew Dillon |
|---|---|
| Full name | HAMMER2 |
| Introduced | June 4, 2014 with DragonFly BSD 3.8 |
| Features | |
| File system permissions | UNIX permissions |
| Transparent compression | Yes |
| Transparent encryption | Planned |
| Data deduplication | Live |
| Other | |
| Supported operating systems | DragonFly BSD |
HAMMER2 is a successor to the HAMMER filesystem, redesigned from the ground up to support enhanced clustering. HAMMER2 supports online and batched deduplication, snapshots, directory entry indexing, multiple mountable filesystem roots, mountable snapshots, a low memory footprint, compression, encryption, zero-detection, data and metadata checksumming, and synchronization to other filesystems or nodes. It lacks support for extended file attributes (xattr).
History[edit]
The HAMMER2 file system was conceived by Matthew Dillon, who initially planned to bring it up to minimal working state by July 2012 and ship the final version in 2013.[1][2] During Google Summer of Code 2013 Daniel Flores implemented compression in HAMMER2 using LZ4 and zlib algorithms.[3][4] On June 4, 2014, DragonFly 3.8.0 was released featuring support for HAMMER2, although the file system was said to be not ready for use.[5] On October 16, 2017, DragonFly 5.0 was released with bootable support for HAMMER2, though file-system status was marked as experimental.[6]
HAMMER2 had a long incubation and development period before it officially entered production in April 2018, as the recommended root filesystem in the Dragonfly BSD 5.2 release.[7]
Dillon continues to actively develop and maintain HAMMER2 as of June 2020.
See also[edit]
References[edit]
- ^ Dillon, Matthew (2017-07-24). "DESIGN document for HAMMER2 (24-Jul-2017 update)" (Mailing list).
- ^ Dillon, Matthew (2011-05-11). "HAMMER2 announcement" (Mailing list).
- ^ "DragonFly BSD 5.0: HAMMER2 a 900 000 procesů".
- ^ "Block compression feature in HAMMER2". GSoC 2013. Retrieved 2014-06-05.
- ^ "DragonFly Release 3.8". DragonFly BSD. 2014-06-04. Retrieved 2014-06-05.
- ^ "DragonFly Release 5.0". DragonFly BSD. 2017-10-16. Retrieved 2017-10-16.
- ^ "DragonFly BSD 5.2". Dragonfly BSD Project. 9 April 2018. Retrieved 11 April 2018.