New Scrub Code - "To fix a longstanding bug (6343667, scrub/resilver has to start over when snapshot is taken), I ended up rewriting the ZFS scrub code (putback in OpenSolaris build 94). Mark Maybee and I were already working on "bp (block pointer) rewrite (or relocate)", functionality that will allow us to traverse all the blocks in the pool and move them around." - Matthew Ahrens