Closed
Description
Describe the feature would like to see added to OpenZFS
Performance of RAIDZ expansion could be improved.
How will this feature improve OpenZFS?
Currently the RAIDZ expansion performance is very slow and it can take several days to add a single large drive.
Improving expansion performance would result in a shorter period of degraded FS performance for users.
Expanding by mote than a single drive is not currently supported, so to add a few new drives to a pool can take weeks.
Additional context
There was discussion on this matter during development of the RAIDZ expansion feature where it was noted that performance is very slow, and the opinion of the developer was that it wouldn't be difficult to improve after the feature has landed.
Maybe it could be considered an item for some near-term follow-up on the landing of the new feature?