Chapter 9: Managing Logical Drives and Hot Spares 79

Changing the Write Cache Setting

The write cache setting determines when data is stored on a disk drive
and when the controller communicates with the operating system.
Disabled (write-through)—The controlle r sends (or writes) the data
to a disk driv e, then sends c onfirmation to the operating system that
the data was received. Use this setting when performance is less
important than data p rotection.
Enabled (write-back)—The controller sends confirmation to the
operating system that the data was rec eiv ed, then writes the data to a
disk drive. Use this setting when performance is more important
than data protection and you aren’t using a battery-backup cache.
Enabled is the default setting.
Enabled (write-back) when protected by battery—The controller
sends confirmation to the operating system that the data was
received, then writes the data to a disk drive. Use this setting if y ou
are using a battery-backup cache and performance is more
important than data protection.
Note: (RAID 10, 50, and 60 only) All logical drives within a RAID 10/
50/60 logical drive must have the same write cache setting—either all
write-through or all write-back.
To quickly change the write cache setting, click the logical drive you
want; then, in the menu bar, select Actions, click C onfigure write cache,
then select Enabled or Disabled as required.

Changing the Stripe Size

The stripe size is the amount of data (in KB) written to one partition
before the controller moves to the next partition in a logical drive.
Stripe size options vary, depending on your controller. Normally, the
default stripe size provides the best performance.
For RAID 6 and RAID 60 logical drives, the mor e disk drives there are
in the logical dri ve, the fewer the stripe size options.