On Wed, October 1, 2008 10:18, Joerg Schilling wrote: > SATA and SAS disks usually base on the same drive mechanism. The seek > times are most likely identical. > > Some SATA disks support tagged command queueing and others do not. > I would asume that there is no speed difference between SATA with command > queueing and SAS.
I guess the meaning in my e-mail wasn't clear: because SAS drives are generally more expensive on a per unit basis, for a given budget, you can buy fewer of them than SATA drives. To get the same storage between capacity with SAS drives and SATA drives, you'd probably have to put the SAS drives in a RAID-5/6/Z configuration to be more space efficient. However by doing this you'd be losing spindles, and therefore IOPS. With SATA drives, since you can buy more for the same budget, you could put them in a RAID-10 configuration. While the individual disk many be slower, you'd have more spindles in the zpool, so that should help with the IOPS. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
