User's Manual

The cache policies are:

• Enabled — Disk Cache Policy is enabled.

• Disabled — Disk Cache Policy is disabled.

NOTE: The default setting for Disk Cache Policy for virtual disks based on SATA drives is Enabled;

and for virtual disks based on SAS drives is Disabled.

NOTE: For SAS 6i/R and PERC H200 family of controllers, the Disk Cache Policy setting is available

only after creating the virtual disk.

Background Initialization On PERC Controllers

On PERC controllers, background initialization of a redundant virtual disk begins automatically within 0 to

5 minutes after the virtual disk is created. The background initialization of a redundant virtual disk

prepares the virtual disk to maintain redundant data and improve write performance. For example, after

the background initialization of a RAID 5 virtual disk completes, the parity information is initialized. After

the background initialization of a RAID 1 virtual disk completes, the physical disks are mirrored.

The background initialization process helps the controller identify and correct problems that may occur

with the redundant data later. In this regard, the background initialization process is similar to a check

consistency.

The background initialization should be allowed to run to completion. If canceled, the background

initialization automatically restarts within 0 to 5 minutes. Some processes such as read and write

operations are possible while the background initialization is running. However, other processes such as

creating a virtual disk, cannot be run concurrently with background initialization. These processes cause

the background initialization to cancel.