OpenZFS Developer Summit (encryption, resilvering, ...)

[fracai]

I recently stumbled across video from the Developer Summit from earlier this year and there is a lot of interesting stuff going on there.
https://www.youtube.com/playlist?list=PLaUVvul17xSfmOrhQ_f6gqMNNuJvnKEqZ
http://open-zfs.org/wiki/OpenZFS_Developer_Summit
https://www.ixsystems.com/blog/openzfs-devsummit-2016/

The first two that have jumped out to me are ZFS Native Encryption and Scrub/Resilver Performance. There's a pull request for the native encryption that looks like there are some regressions to resolve. The Scrub Performance looks very impressive (basically scanning the disk to process blocks as they're written out on disk rather than the order they were recorded) with sometimes dramatic improvements.

Given the iX Systems post I guess I missed all this when it was posted a month ago, but I haven't seen any discussion on the forum either.

Here's to a speedy development for these and the other features.

 

[Arwen]

One thing under development with OpenZFS is vDev removal. At present, the work is to
remove either plain vDev, (single disk or file), or single mirror vDev.

The scheme as written does not support RAID-Zx vDevs, but they are talking about it. However,
it appears that the scheme for RAID-Zx would only work is you had 2 identical type and
widths of RAID-Zx. Meaning that if you have a 4 disk RAID-Z2 and a 6 disk RAID-Z2, and
wanted to remove either one, it would not work.

Last, this scheme as it exists now uses indirect blocks, which will exist for the life of the pool.
Unless the files/directories referenced are deleted. These indirect blocks will take up memory,
and read into memory every time a pool with that feature active is imported.

Please note that this is preliminary information, subject to change. (And of course, subject to
my mis-interpretation.)