> What happens when a sub-block is missing (single disk failure)? Surely > it doesn't have to discard the entire checksum and simply trust the > remaining blocks?
The checksum is over the data, not the data+parity. So when a disk fails, the data is first reconstructed, and then the block checksum is computed. > Also, even if it could read the data from a subset of the disks, isn't > it a feature that every read is also verifying the parity for > correctness/silent corruption? It doesn't -- we only read the data, not the parity. (See line 708 of vdev_raidz.c.) The parity is checked only when scrubbing. This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
