On Tue, 10 Mar 2009, Moore, Joe wrote:
As far as workload, any time you use RAIDZ[2], ZFS must read the entire stripe (across all of the disks) in order to verify the checksum for that data block. This means that a 128k read (the default zfs blocksize) requires a 32kb read from each of 6 disks, which may include a relatively slow seek to the relevant part of the spinning rust. So for random I/O, even though the data is striped
This is not quite true. Raidz2 is not the same as RAID6. ZFS has an independent checksum for its data blocks. The traditional RAID type technology is used to repair in case data corruption is detected.
Bob -- Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
