HP StorageWorks XP12000 Manuale d'uso - Pagina 16

b. Priority mode

Required cache size = (Number of addresses × (128 × (512 + 16) ) ) ÷ 1,024

Units are KB

NOTE:

If a RAID-5 or RAID-6 volume area is changed from priority mode to bind mode and no cache is

added, only 33 percent of the user data fits into the area previously assigned for priority mode. The

remaining 67 percent is used to save read/write data. If a RAID-1 volume area is changed from priority

mode to bind mode and no cache is added, only 50 percent of the user data fits in the area previously

assigned for priority mode. The remaining 50 percent is used to save read/write data. Changing the

mode without cache extension requires Cache LUN XP reconfiguration.

Starting Cache LUN XP

Click Cache LUN in the left pane. The Cache LUN pane appears.

Figure 3

This pane lists the following items.

Use this drop-down list to select a cache logical partition (CLPR). The CLPR drop-down list displays the CLPR

number and CLPR name.

When you select a CLPR, volumes belonging to the selected CLPR and cache information appear in the

LDEV tree.

NOTE:

If you administer only one CLPR, the CLPR drop-down list is not available.

Select or clear this check box to enable or disable the pre-staging function:

•

If you select this check box, set the Prestaging Mode to Yes and click Apply. A non-pre-staging

operation will be performed and then a pre-staging operation will be performed.

Cache LUN XP for the XP10000/XP12000