More Arms or Separate Arrays for tempdb?

I am faced with the enviable position of having 15 SAN drives available for use by tempdb and am seeking the absolute highest performance.



Separate arrays or more arms?

Options:


Four tempdb files spread across
One big RAID 10 array with 14 spindles (5 in enclosure 1 and 9 in enclosure 2)

Three tempdb files, each one on its own array
Three RAID 10 arrays on 4 spindles each

Four tempdb files spread across
Three RAID 10 arrays on 4 spindles each

Thoughts? Experiences? Metrics?

Jeff,

We went with RAID 0 + 1 rather than 1 + 0 for the increase in performance. I don't know how many spindles they spread that across. For further redundancy and disaster recovery planning, the entire SAN is replicated to another SAN in a seperate data center a half mile down the road.

Gregg

If that's a quad systerm, you should go with 4 arrays, I'd say...

Whats the speed of your fibre interface and how many interfaces do you have on your SAN box and servers? For example if you have only one 1GBit interface on your SAN, 15 disks in one array, each disk capable of transferring a continuous 50MB/S. That configuration would probably force the interface to bottleneck and cause a performance drop. In this example it would be better to have several arrays, with 5 disks per array.