We plan to use an Storage Bay IBM FastT200 connected to the server by Fiber Channel. We test the package which is working right. My question is : In this configuration, do you think it is always necessary to organize the database as Navision says (RAID 1, several disks, several database files, …) or let the bay do its job. I think that the constraints are due to the fact that usually the data reside on the server.
There are obvious reasons for keeping some level of data redundancy, of course. But whether it is necessary to complicate the setup of the database by striping it over several disks as traditionally recommended by Navision is purely a question of performance. As Navision’s recommendations are likely to be based on experience with “traditional” disk configurations, those recommendations may not apply to (or be necessary for) today’s more advanced storage systems. So if you have a possibility of performing your own throughput tests on the FastT200, I would definitely recommend you to base your decision on those tests. However, the basic logic behind the recommendation remains true: The Navision Server needs to access the physical database files several “places” (database blocks) per database operation. As those accesses are inherently striped across the database parts, adding more parts (on different drives) will reduce the number of random accesses per disk. This will shorten the total duration of the database operation and speed up the system. - Jens
It is what I thought, Thank’s for your answer. Jean-Marc