On Wed, Jun 28, 2006 at 11:15:34AM +0200, Robert Milkowski wrote: > DV> If ZFS is providing better data integrity then the current storage > DV> arrays, that sounds like to me an opportunity for the next generation > DV> of intelligent arrays to become better. > RM> Actually they can't. RM> If you want end-to-end data integrity it has to be checked on a RM> server.
But Joe makes a good point about RAID-Z and iSCSI. It'd be nice if RAID HW could assist RAID-Z, and it wouldn't take much to do that: parity computation on write, checksum verification on read and, if the checksum verification fails, combinarotial reconstruction on read. The ZFS system (iSCSI client) would still have to verify the checksum on read... ...but leaving parity computation/reconstruction to the iSCSI server would greatly cut down the amount of I/O needed for RAID-Z to something similar to that needed for HW RAID-5. Sure, I don't expect HW-assisted RAID-Z anytime soon, nor iSCSI extensions for server-assisted RAID-Z. But at least iSCSI protocol extensions could be pursued now. Nico -- _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss