Requirements for raid manager, Assessing requirements, Calculating maximum number of pairs – HP XP Business Copy Software User Manual
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Figure 23 Total Capacity of XP Business Copy Volumes (Example 3)
Requirements for RAID Manager
To use RAID Manager for XP Business Copy operations, you need to have one volume for RAID
Manager’s command device. For details about how to set the command device, see the HP
StorageWorks XP RAID Manager User Guide.
Assessing Requirements
This section describes the assessments about XP Business Copy operations, such as how many
pairs you are going to create or how to decide the settings like copy pace and paths.
Calculating Maximum Number of Pairs
When you create XP Business Copy pairs, resources called differential tables and pair tables will
be required. The number of available differential tables and pair tables in one storage system
depends on whether additional shared memory is installed or not.
describes
the differential and pair tables that are supported by the options for adding shared memory.
Table 14 Additional Shared Memory for Differential Tables
Number of Volumes in
Storage system
Number of Pair Tables
Number of
Differential
Tables
Additional Shared Memory for XP Business
Copy
1,024
0
0
No additional shared memory for XP Business
Copy
16,384
8,192
26,176
Additional shared memory for XP Business
Copy is installed
16,384
8,192
57,600
Extension 1
65,536
16,384
104,768
Extension 2
131,072
16,384
146,688
Extension 3
1
131,072
16,384
209,600
Extension 4
1
1
This can be used only in HP StorageWorks 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
). For example, if additional shared memory for XP Business Copy is installed (second line
Assessing Requirements
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