HP StorageWorks XP24000 Disk/Cache Partition User's Guide, v01 (T5214-96004, June 2007)

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 par tition function is referred to

as the C LPR. Up to 32 CLPRs including CLPR0 which is provided as a default can be created in one

subsystem. See “Cache Logical Pa rtition Operations”onpage35for creating CLPR.

Note:

Though you usually need the license key to use the Cache Logical Par tition function of Disk/Cache

Partition, you may create up to 4 CLPRs (including CLPR0) without the license key.

Figure 2 An Example of Ca che Logical Partition

To creat

e a

CLPR, a lloc ate the parity groups to CLPR. For instructions on allocating parity g roups, see

“Perfo

rming Disk/Cache Partition Operations” on page 33.

To crea

te 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 Stor

ageWorks XP24000 Remote Web Console User’s Guide.

To mana

ge the

cache memory by using the functions of HP StorageWorks XP Cache Residency Manager,

you ca

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

you

create a CLPR, use the following formula to calculate the cache capacity which is allocated

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