> Generally speaking, striping mirrors will be faster > than raidz or raidz2, > but it will require a higher number of disks and > therefore higher cost to > The main reason to use > raidz or raidz2 instead > of striping mirrors would be to keep the cost down, > or to get higher usable > space out of a fixed number of drives.
While it has been a while since I have done storage management for critical systems, the advantage I see with RAIDZN is better fault tolerance: any N drives may fail before the set goes critical. With straight mirroring, failure of the wrong two drives will invalidate the whole pool. The advantage of striped mirrors is that it offers a better chance of higher iops (assuming the I/O is distributed correctly). Also, it might be easier to expand a mirror by upgrading only two drives with larger drives. With RAID, the entire stripe of drives would need to be upgraded. -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss