Asus M3A78-EMH HDMI - Manual (Page 109)

Chapter 6: Technology Background
103
Choosing Stripe Block Size
For RAID 0, 5 and 10 logical drives, the stripe block size value can be set to
64 KB or 128 KB. 64 KB is the default. Your choice will directly affect
performance. There are two issues to consider when selecting the stripe block
size.
•
Choose a stripe block size equal to or smaller than the smallest cache buffer
found on any physical drive in your logical drive. A larger value slows the
logical drive down because physical drives with smaller cache buffers need
more time for multiple accesses to fill their buffers.
• If your data retrieval consists of fixed-size data blocks, such as some
database and video applications, choose that data block size as your stripe
block size.
Generally speaking, email, POS, and webservers prefer smaller stripe block
sizes. Video and database applications prefer larger stripe block sizes.
Gigabyte Boundary
The Gigabyte Boundary feature is designed for logical drives in which a drive has
failed and the user cannot replace the drive with the same capacity or larger.
Instead, the Gigabyte Boundary feature permits the installation of a replacement
drive that is slightly smaller (within 1 gigabyte) than the remaining working drive
(for example, an 80.5-GB drive would be rounded down to 80 GB). This can be
helpful in the event that a drive fails and an exact replacement model is no longer
available.
Gigabyte Boundary is available for all RAID levels. If you split the capacity of your
physical drives between two logical drives, you can choose Gigabyte Boundary
for the second logical drive. See “Creating a Logical Drive” on page 65.
Initialization
Initialization is the process of setting all of the data bits on all of the physical
drives to zero. This has the effect of erasing any existing data from the drives.
This action is especially helpful in creating accurate parity in logical drives with
more than four drives.
Fast Initialization is available for all RAID levels and JBOD. Full Initialization is
available for RAID 1, 5, and 10. See “Creating a Logical Drive” on page 65.
The Full Initialization process begins immediately after the logical drive is created
and can take some time to finish, depending on the size of the physical drives in
your logical drive. Your logical drive is available while initialization is in progress.