Users guide

Intel® RAID Software User Guide 80
Figure 24. Create Virtual Drive – Advanced
13. Select Initialize,
and press OK.
The new virtual drive is created and initialized.
7.7.1 Selecting Additional Virtual Drive Properties
This section describes the following additional virtual drive properties that you can select
while you create virtual drives. Change these parameters only if you have a specific
reason for doing so. It is usually best to keep them at their default settings.
• Strip Size – The strip size is the portion of the stripe that resides on a single virtual
drive in the drive group. Strip sizes of 64 KB, 128 KB, 256 KB, 512 KB, or 1 MB
are supported.
• Read Policy – Specify one of the following options to specify the read policy for
this virtual drive:
— Nor
mal – Read ahead capability lets the controller read sequentially ahead of
requested data and store the additional data in cache memory, thereby
anticipating that the data will be needed soon. This process speeds up reads for
sequential data, but there is little improvement when the computer accesses
random data.
— Ahead –
Disables the read ahead capability.
• Write Policy – Select one of the following options to specify the write policy for
this virtual drive:
— W
rite Thru – In this mode, the controller sends a data transfer completion
signal to the host when the drive subsystem has received all the data in a
transaction. This option eliminates the risk of losing cached data in case of a
power failure.
— Wr
ite Back – In this mode, the controller sends a data transfer completion
signal to the host when the controller cache has received all the data in a
transaction.