Compaq ProLiant 6500 Compaq Parallel Database Cluster Model PDC/05000 for Orac - Page 92

4-18 Compaq Parallel Database Cluster Model PDC/O5000 for Oracle8i and Windows 2000 Administrator Guide Selecting the Appropriate RAID Level Many factors will affect the RAID levels you select for your cluster database. These include the specific availability, performance, reliability, and recovery capabilities required from the database. Each cluster must be evaluated individually by qualified personnel. The following general guidelines apply to RAID selection for a PDC/O5000 cluster using Oracle8i Parallel Server: I Oracle recommends that some form of disk fault tolerance be implemented in the cluster. I In order to ease the difficulty of managing dynamic space allocation in an OPS raw volume environment, Oracle recommends the creation of "spare" raw volumes that can be used to dynamically extend tablespaces when the existing datafiles approach capacity. The number of these spare raw volumes should represent from 10 to 30 percent of the total database size. To allow for effective load balancing, the spares should be spread across a number of disks and controllers. The database administrator should decide, on a case by case basis, which spare volume to use based on which volume would have the least impact on scalability (for both speedup and scaleup).