OpenZFS Eyes Faster Scrub, Improved Compression, uZFS, Better Performance

Taking place yesterday and today in San Francisco has been the annual OpenZFS Developer Summit. Talks this year ranged from how Amazon AWS is making use of OpenZFS to a number of optimizations and improvements currently being tackled by open-source developers.

For those interested in the OpenZFS file-system, talks for this year's developer summit included discussing Zvol performance, refining OpenZFS compression, running ZFS in user-space, faster ZFS scrub and other work being pursued, shared L2arc, and other interesting talks. Taking place this afternoon meanwhile is their annual OpenZFS hackathon.

The Zvol talk by Tony Hutter included looking at the blk-mq performance benefits for non-O_DIRECT writes along with a number of other optimizations being pursued at LLNL. The blk-mq support in Zvol has been merged and as part of that patch series the sequential dd performance to one Zvol with non-O_DIRECT went from 292 MB/s writes to 453 MB/s while reads went from 453 MB/s to 885 MB/s.

The user-space ZFS work was presented by IOMesh with "uZFS" as an alternative to existing FUSE-based ZFS drivers. The intentions with uZFS are to keep it more isolated, easily integrate into other storage systems, make use of user-space tooling, and more easily develop/upgrade/debug. The uZFS implementation performs much better than zfs_fuse but still often behind the kernel ZFS driver in various tasks.

To learn more about these 2022 OpenZFS happenings, see the developer summit Wiki page that contains links to the various presentation slides.