Compaq Parallel Database Cluster Model PDC/O1000 for Oracle8i and Windows 2000 Administrator Guide

4-16 Compaq Parallel Database Cluster Model PDC/O1000 for Oracle8i and Windows 2000 Administrator Guide
Compaq Confidential – Need to Know Required
Writer: John Blackburn Project: Compaq Parallel Database Cluster Model PDC/O1000 for Oracle8i and Windows 2000 Administrator Guide
Comments:
Part Number: 225083-002 File Name: e-ch4 Cluster Planning.doc Last Saved On: 6/11/01 11:20 AM
Selecting the Appropriate RAID Levels
Many factors affect which 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 cluster with
RA4000/RA4100 Arrays using Oracle8i Parallel Server:
■ Oracle recommends that some form of disk fault tolerance be
implemented in the cluster.
■ In order to ease the difficulty of managing dynamic space allocation in
an Oracle Parallel Server 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).