HP XP P9000 Cache Partition User Guide (AV400-96477, August 2012)

Restrictions
The following operations are not allowed when multiple CLPRs are involved:
• Creating LUSE volumes across multiple CLPRs. If you forcibly perform this operation and create
a LUSE across multiple CLPRs, the LUSE volumes cannot be used for Continuous Access
Synchronous or Continuous Access Synchronous Z pair volumes.
• Business Copy Quick Restore operations that affect multiple CLPRs.
• Auto LUN manual migration operations that affect multiple CLPRs.
• A parity group containing LDEVs assigned to Cache Residency cache extents (cache areas)
cannot be migrated to another CLPR. See the HP XP P9000 Performance for Open and
Mainframe Systems User Guide for more information about cache extents.
• If you are using Continuous Access Journal, Continuous Access Journal data volumes and
journal volumes can belong to different CLPRs. All journal volumes in the same journal must
belong to the same CLPR. If not, an error occurs.
Guidelines
• Install any needed additional cache memory before partitioning cache. It will be difficult to
add additional cache memory after partitioning cache into CLPRs.
• If the cache capacity of defined CLPR is decreased by the Cache Residency cache area, cancel
Cache Residency bind mode setting, change the cache capacity of CLPR, and then set the
bind mode or priority mode again.
• Best practice is to create cache logical partitions either during the initial installation and setup
or during a maintenance window, because cache logical partition operations can significantly
degrade host performance. If you must perform such operations on a production machine,
use Performance Monitor to verify that the write pending rate, including spikes, is well below
30%.
The table below shows CLPR names set by default to associated CLPR numbers. Because CLPR
names are reserved, they cannot be set to alternative CLPR numbers. For example, "CLPR2" cannot
be set to the CLPR number 1.
CLPR nameCLPR numberCLPR nameCLPR number
CLPR1616CLPR00
CLPR1717CLPR11
CLPR1818CLPR22
CLPR1919CLPR33
CLPR2020CLPR44
CLPR2121CLPR55
CLPR2222CLPR66
CLPR2323CLPR77
CLPR2424CLPR88
CLPR2525CLPR99
CLPR2626CLPR1010
CLPR2727CLPR1111
CLPR2828CLPR1212
CLPR2929CLPR1313
8 Creating virtual cache partitions