Follow-up: I read up on the ashift thing and it looks like the drives I'm using are NOT ones that lie about the physical/logical sectors. So I wouldn't need to ashift. Which is good because I'd have to rebuild the pool... On Mon, 11 Nov 2013, Thomas Lunde wrote: > > Bit flips like this helped me to discover that two of my 10 SATA cables were marginal. > > Since these are >2T drives, did you do anything with ashift? Depending on which ZFS implementation you're using, this question might not make sense? > > An array of drives where some are faking 512 byte sectors and ( some are really using 512 byte sectors OR some are using 4K sectors ) can cause abysmal performance. > > Thomas > > _______________________________________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/mailman/listinfo/tclug-list >