It's called scrubbing.
Did you mean to reply to my above question? If so, I'm unclear as to what you're trying to get across.
Is ZFS scrubbing different than the other RAIDs' (scheduled or schedulable) reads of the entire array, other than nomenclature?
I'm not sure if you meant to imply that ZFS is different from standard RAID in this regard, but it doesn't seem as though it is.