spreading disk I/O ,which is better??

Hi,

I have the following problem, I have a heavily used tablespace of 8Gb and IBM SSA disks. I can't use logical volume striping. I have a choise of making one tablespace on a 9Gb disk or use filesystem striping on 4 disks of 2.2 Gb. The last option means making several datafiles on the 4 disks. If the last option is the best? and if so, what is wise? making a lot of datafiles (say 200Mb each) and file 1-4 on disk 1-4 , file 5-8 again on the 4 disk's and so on until I have 9Gb or just 4 datafiles on the 4 disk's .
Is the choice different when dealing with indexes or tables (indexes tend to be accessed more randomly)?
The disk's are mirrored so reading will be fast but writing will be slower. SSA disk's are supposed to be very fast, IBM tell's me a single SSA disk can compete with striped FW SCSI disk's. I can make a group of disk's in which the other disk's won't influence this disk, so the SSA adapter won't be a problem. For people who know SAP , it's the sappcl2 data and index tablespace of the payroll.

Thanks for helping!

regards,

Wijbrand Pauw Received on Sat Oct 11 1997 - 00:00:00 CDT