ZoneFS File-System To See Some Improvements With Linux 5.19

Back in 2019 Western Digital announced their work on ZoneFS as a new Linux file-system just designed for specialty use-cases and running on zoned block devices. There hasn't been much code churn around ZoneFS in a number of kernel releases since it was merged back in 2020 while for Linux 5.19 this summer a number of fixes/improvements have been queuing up.

Western Digital's ZoneFS was mainlined back in Linux 5.6 but since then there hasn't been too much notable additions to this file-system driver code. ZoneFS isn't a conventional POSIX-compliant file-system but more akin to offering a raw block device with zoned block semantics. ZoneFS exposes the zones of a zoned block device as files and grouped by zone type. It's a very different approach from conventional Linux file-systems with many of them offering zoned block device support. The intent is for ZoneFS to be used for specialized use-cases such as for better handling of log-structured merge tree structures used by the likes of RocksDB and LevelDB. More technical details on ZoneFS can be found via the kernel documentation.

A Western Digital visual on ZoneFS.

Western Digital's Damien Le Moal who has been leading much of the ZoneFS work since its upstreaming and serving as the maintainer has established a "for-5.19" Git branch. In there he has been queuing a number of fixes and other improvements that will be destined for Linux 5.19 this summer. Among that work is exposing open zone resource information via sysfs, active seq file accounting, and other improvements.

We'll see as well what more patches may get queued into this for-5.19 branch in the next few weeks with the Linux 5.19 merge window not opening up until the end of May. In any event it's good to see WD still working on improvements to ZoneFS.