HP StorageWorks XP Remote Web Console Software - Manual (Page 15)

down the read/write speed under the influence of data access amount of branch A. The hosts of other
branches always can use up to 40 Gbytes cache area.
The virtual cache memory that is partitioned by using the cache logical partition function is referred to
as the CLPR. Up to 32 CLPRs including CLPR0 which is provided as a default can be created in one
subsystem. See “ Cache Logical Partition Operations ” on page 35 for creating CLPR.
Note: Though you usually need the license key to use the Cache Logical Partition function of Disk/Cache
Partition, you may create up to 4 CLPRs (including CLPR0) without the license key.
Figure 2 An Example of Cache Logical Partition
To create a CLPR, allocate the parity groups to CLPR. For instructions on allocating parity groups, see
“ Performing Disk/Cache Partition Operations ” on page 33.
To create a CLPR and manage it, you need a user authority for storage sys-
tem, that is, Storage Administrator. For details on a Storage Administrator, see
“ Storage Administrator and Storage Partition Administrator Privileges ” on page 17 in this manual and the
HP StorageWorks XP24000 Remote Web Console User’s Guide.
To manage the cache memory by using the functions of HP StorageWorks XP Cache Residency Manager,
you can set up the cache area for Cache Residency Manager in each CLPR. For details on Cache
Residency Manager, see the HP StorageWorks XP24000 Remote Web Console User’s Guide.
• Criteria of the capacity when you create a CLPR
If you create a CLPR, use the following formula to calculate the cache capacity which is allocated
to the CLPR.
Cache capacity (GB)
=Recommended cache capacity (GB)+
↑(Cache Residency capacity(MB)/2,048)↑ x2GB
For information on the recommended cache capacity, see Table 3 on page 18.
XP24000 Disk/Cache Partition User's Guide 15