HP StorageWorks XP Remote Web Console Software - Manual (Page 18)

18 Overview of Compatible PAV Operations
NOTE: If you will be using static Compatible PAV, determine on which devices I/O requests are likely to
converge, and then assign more aliases to those base devices. If not, Compatible PAV might not be able to
provide much improvement in host access to data in the XP1024/XP128/XP12000/XP10000.
Figure 3 Static Compatible PAV
Dynamic Compatible PAV
When dynamic Compatible PAV is used, the number of aliases for a base device may change as the
number of I/O requests to the device changes. If I/O requests converge on several base devices, the
number of aliases for these devices may increase, while the number of aliases for other base devices may
decrease. Dynamic Compatible PAV operations can balance workloads on base devices and optimize the
speed for accessing data in the XP1024/XP128/XP12000/XP10000.
The following figure shows an example of dynamic Compatible PAV operations. Each of the three base
devices (x10, x11, and x12) was originally assigned two aliases. In this example, as I/O requests converge
on base device x10 (shown by the large arrow), the number of aliases for device x10 increases to four,
while the number of aliases for base device x11 and x12 decreases to one.