HP XP P9000 Performance Advisor Software v6.0 User Guide

A Appendix A
Storage management logical partitions (SLPRs)
A disk array can be shared with the multiple organizations and with multiple departments within
an enterprise. Therefore, multiple administrators might manage a single disk array. This circumstance
creates the potential for an administrator to destroy volumes of other organizations, and it can
complicate and increase the difficulty of managing the disk array.
Use Disk/Cache Partition to allocate all components of one disk array (all ports and CLPRs) to
virtual disk arrays called SLPRs. You can create up to 31 SLPRs in one disk array. Each virtual disk
array can be accessed only by its administrator. This approach eliminates the risk of an administrator
destroying volumes from other organizations and of data leaks among organizations.
In a non-partitioned environment, a full array is considered one single partition SLPR0. After the
disk array is partitioned, SLPR0 becomes the unpartitioned portion of the disk array. Similarly,
CLPR0 contains all parity groups (PGs) and cache in the non-partitioned environment. After the
disk array is partitioned, CLPR0 contains the remaining PGs and cache that are not allocated to
other CLPRs.
Figure 35 Example of an SLPR
“Example of an SLPR” (page 358) displays an example of one disk array partitioned into two virtual
disk arrays. Each virtual disk array is allocated to one enterprise. Enterprise A's disk array
administrator can manage enterprise A's virtual disk array, but cannot manage enterprise B's disk
array. Similarly, enterprise B's disk array administrator can manage enterprise B's virtual disk
array, but cannot manage enterprise A's disk array.
Cache logical partitions (CLPRs)
When one disk array is shared with multiple hosts, and one host reads or writes a large amount
of data, the host's read and write data occupies a large area in the disk array's cache memory.
In this situation, the I/O performance of other hosts decreases because the hosts must wait to write
to cache memory. To prevent this situation, CLPR partitions the disk array's cache memory.
Partitioned cache memories are used as virtual cache memories, and each is allocated to each
358 Appendix A