HP Surestore Disk Array 12h System Administrator's Guide for HP-UX, MPE, and W - Page 120

Managing the HP SureStore E Disk Array 12H on MPE Tips for Configuring the Disk Array On MPE Configuration Option Number of disk drives Unallocated disk array capacity Impact on Performance and Capacity Performance. Increase the number of disk mechanisms in the disk array for maximum performance. As the number of individual disks is increased, the number of potential I/Os that can be performed simultaneously increases as well. This will improve performance in environments that place heavy I/O demand on the disk array. Capacity. The capacity of a disk array that is fully populated with disk mechanisms can only be increased by replacing lower capacity disks with higher capacity disks. Performance. Unallocated capacity is used as additional RAID 0/1 space. The amount of RAID 0/1 space required to maintain optimal performance is determined by the write working set parameter. Capacity. To create the maximum amount of storage capacity, allocate all available capacity to LUNs. MPE 120