Eleven,
> In particular - could someone tell me if those iostat
> values can tell if I'm close to upper performance boundary
> of fast SCSI (Ultra 320, 15k RPM) disks?
It's quite possible that you need to improve your disk array; certainly I
would have spec'd a lot more disk than you're using (like raid 0+1 with 6
disks or RAID 5 with seven disks).
However, there's the other end as well; it's quite possible that your queries
are doing seq scans and other disk-intensive operations that could be
avoided. Have you analyed this at all?
--
-Josh Berkus
Aglio Database Solutions
San Francisco