ZFS raidz expansion is coming(github.com)
github.com
ZFS raidz expansion is coming
https://github.com/openzfs/zfs/pull/15022
3 comments
Could it be related to the following?
> After the expansion completes, old blocks remain with their old data-to-parity ratio (e.g. 5-wide RAIDZ2, has 3 data to 2 parity), but distributed among the larger set of disks. New blocks will be written with the new data-to-parity
> After the expansion completes, old blocks remain with their old data-to-parity ratio (e.g. 5-wide RAIDZ2, has 3 data to 2 parity), but distributed among the larger set of disks. New blocks will be written with the new data-to-parity
Sounds like it, but I wonder if they'll be able to add a "final pass rewrite" that would scrub it clean.
Interesting - this indicates that the resulting vdev is on-disk different than a fresh vdev would be. Normally when you have a RAID expansion/level change, the format during the conversion is different, but when it is complete the on-disk is identical to it having always been that way.