HP XP20000XP24000 Disk Array - Manual (Page 13)

To find fast hard disk drives, display the Auto LUN window and check classes ( Figure 4 on page 13).
Classes indicate disk access speed for parity groups. Fastest parity groups (or groups of fastest disks)
belong to class A. Parity groups in class B are not as fast as parity groups in class A, but are faster than
parity groups in class C. Parity groups in higher classes (such as class A) provide faster disk access
than parity groups in lower classes (such as class C). Note: In the storage system documentation, the
terms class and HDD class mean the same thing.
Figure 4 Classes and Parity Groups that Appear in the Auto LUN Window
Next, you should choose a low-usage parity group from the fast parity groups. You can find low-usage
volumes in the Auto LUN Window (see Figure 5 on page 13 below).
Figure 5 Parity Group Usage Displayed in the Auto LUN Window
Next, display the contents of the low usage parity group and then look for disk areas preceded by the
icons. From the disk areas, choose the destination disk area
XP24000 Auto LUN Software User's Guide 13