>True - I'm a laptop user myself. But as I said, I'd assume the whole disk >would fail (it does in my experience).
That's usually the case, but single-block failures can occur as well. They're rare (check the "uncorrectable bit error rate" specifications) but if they happen to hit a critical file, they're painful. On the other hand, multiple copies seems (to me) like a really expensive way to deal with this. ZFS is already using relatively large blocks, so it could add an erasure code on top of them and have far less storage overhead. If the assumed problem is multi-block failures in one area of the disk, I'd wonder how common this failure mode is; in my experience, multi-block failures are generally due to the head having touched the platter, in which case the whole drive will shortly fail. (In any case, multi-block failures could be addressed by spreading the data from a large block and using an erasure code.) This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss