HP XP7 External Storage for Open and Mainframe Systems User Guide (TK914-96001)

Minimum LDEV capacity and Base LDEV capacity are calculated with the following
formulas.
Minimum LDEV Capacity = Minimum Data Area Capacity \
+ Control Information Area Capacity
Base LDEV Capacity = Base Data Area Capacity \
+ Control Information Area Capacity
For volumes of mainframe systems other than 3390-A and 3390-V, capacities for the
expanded control information area and the adjustment area are also necessary. For
details, see “LDEV capacities per emulation type” (page 17).
If the external volume capacity is less than the minimum LDEV capacity, the emulation
type cannot be specified.
Figure 1 Idea of LDEV capacity
• An external volume whose capacity is more than the base LDEV capacity for the emulation
type results in multiple LDEVs created when the volume is mapped. These LDEVs will have the
base LDEV capacity.
• When using VLL, a maximum 2,048 CVs can be created.
(VLL is not supported for the OPEN-L emulation type.)
• For emulation types other than OPEN-V, usable capacity in the internal volume is the capacity
of the external volume minus control information area capacity.
• Data above the maximum capacity cannot be accessed.
LDEV capacities per emulation type
The following table shows LDEV capacities for each emulation type in units of blocks and cylinders.
The number of cylinders in this section is calculated as:1 cylinder = 1,740 blocks.
Control Information Area
Capacity
Base Area CapacityMinimum Data Area CapacityEmulation Type
(Cylinders)(Blocks)(Cylinders)(Blocks)(Cylinders)(Blocks)
-11,520-4,806,720-72,000OPEN-3Volume for
open systems
-338,880-14,351,040-72,000OPEN-8
-338,880-14,423,040-72,000OPEN-9
-27,360-28,452,960-72,000OPEN-E
Planning external volumes 17