September 13, 2013 \ Ananth TM RAID and SAN configurations Performance of a job (for IBM WebSphere® DataStage®, IBM WebSphere QualityStage™, and IBM WebSphere Information Analyzer) depends on all components being optimized. For RAID (Redundant Array of Independent Disks) and SAN (system area network) configurations, maximum performance is a combination of maximum bandwidth (controllers and disk) and minimized contention. The following guidelines can assist in the configuration of RAID or SAN technologies: Ensure that your database is optimally tuned. Ensure that computers where you install the metadata repository tier and the services tier are on a high-speed network. Minimize contention between temporary (scratch, buffer, and sort) and data file systems. For temporary storage, do not use a network file system (NFS). Consider using the local disk for temporary storage. Minimize contention between the disks and controllers that are associated with IBM Information Server file systems and other applications or servers. Consider isolating multiple mount points to separate high-speed disk interconnects and controllers. Consider the trade-off between the granularity of file systems and the underlying configuration in comparison to the available, unused storage. Do not create overly complex device configurations. These configurations can be difficult to administer and might not offer noticeable performance improvement. If possible, check your configuration with expertise from hardware, storage, operating system, and application (IBM Information Server) personnel. Remember that previous experience in designing I/O systems for nonparallel engines might lead to non-optimal configurations for IBM Information Server. The optimal disk configuration balances cost, complexity, ease of administration, and ultimate performance.