HP XP24000/XP20000 Business Copy Software User Guide (T5213-96034, November 2011)

Table Of Contents
Table 15 Additional Shared Memory for Differential Tables
Number of Volumes inNumber of Pair TablesNumber of
Differential
Additional Shared Memory for XP Business
Copy Storage system
Tables
1,02400No additional shared memory for XP Business
Copy
16,3848,19226,176Additional shared memory for XP Business
Copy is installed
16,3848,19257,600Extension 1
65,53616,384104,768Extension 2
131,07216,384146,688Extension 3
1
131,07216,384209,600Extension 4
1
1
This can be used only in HP XP24000/XP20000 Disk Array.
To install additional shared memory for differential tables, call HP technical support.
If you install additional shared memory for differential tables and pair tables, the maximum
number of pairs is half of the total number of volumes in the storage system (see Table 15 (page
42)). For example, if additional shared memory for XP Business Copy is installed (second line
in Table 15 (page 42)), and when P-VOLs and S-VOLs are in a one-to-one relationship, you
can create up to 8,192 pairs. However, in the case of Extension 2 to Extension 4, the maximum
number of pairs is 16,384, regardless of the total number of volumes in the storage system.
To calculate the maximum number of XP Business Copy pairs, you need to calculate how many
differential tables and pair tables are required to create XP Business Copy pairs, and then compare
the result with the number of differential tables and pair tables in the entire storage system. In
addition to XP Business Copy, the following program products will also use differential tables and
pair tables.
Program products using differential tables
ShadowImage for Mainframe
FlashCopy Mirroring
FlashCopy Mirroring V2
XP Auto LUN
XP Snapshot
Program products using pair tables
ShadowImage for Mainframe
FlashCopy Mirroring
XP Auto LUN
If XP Business Copy and these program products are used in the same storage system, the number
of available differential and pair tables for XP Business Copy pairs will be the total number of
available tables in the storage system minus the tables used by the above program products.
For information about how to calculate the number of differential tables and pair tables that are
required for ShadowImage for Mainframe, see the XP Business Copy™ for Mainframe User Guide:
HP XP24000 Disk Array, HP XP20000 Disk Array. For FlashCopy Mirroring and FlashCopy
Mirroring V2, see the HP XP24000/XP20000 for FlashCopy Mirroring Software User Guide. Also,
see the HP XP24000/XP20000 Auto LUN Software User Guide to calculate the number of
differential tables and pair tables that are required for XP Auto LUN. See the HP XP24000/XP20000
42 Preparing for XP Business Copy Operations