HP StorageWorks XP Business Copy Software user guide: HP XP12000 Disk Array, HP XP10000 Disk Array, HP 200 Storage Virtualization System (T1713-96027, April 2010)

EquationEmulation type
Total number of differential tables per pair = (X ÷ 256) ÷ (Z)
•
(X): Volume capacity (KB)
2
• (Z): Number of slots that can be managed by a differential table (61,312)
NOTE:
Round the result of the calculation up to the nearest whole number.
For example, if the volume capacity (X) is the maximum OPEN-V volume capacity of
3,019,898,880 KB, the total number of differential tables is calculated as follows:
(3,019,898,880 ÷ 256) ÷ 61,312 = 192.40084
When you round up to the nearest whole number, the result is 193. Therefore, the
total number of differential tables for a pair is 193 when the emulation type is OPEN-V.
OPEN-V
1
If the selected volume is a CVS (custom volume size) volume, use the capacity of the custom volume instead of the default
volume capacity for the emulation type. Since the OPEN-L emulation type does not support custom volume operations, you
must use the default volume capacity of OPEN-L for X.
2
1 KB equals 1024 bytes.
Table 3 Number of control cylinders according to emulation types
Number of control cylindersEmulation type
8 (5,760 KB)OPEN-3
27 (19,440 KB)
OPEN-8
OPEN-9
19 (13,680 KB)OPEN-E
7 (5,040 KB)OPEN-L
0 (0 KB)OPEN-V
Table 4 shows the relationship between emulation type, capacity, and differential tables. Table 5
shows the number of differential tables used in OPEN-V.
Table 4 Relationship between emulation type, capacity, and differential tables
Differential tables per
pair
Capacity
1
Emulation type
1Does not depend on capacityOPEN-3
1Up to 2.7GB
OPEN-9 2Up to 5.5GB
3Up to 6.8GB
1Up to 2.7GB
OPEN-E
2Up to 5.5GB
3Up to 8.4GB
4Up to 11.2GB
Business Copy XP (BC) for the Array16