For Raid 1 And Raid 10 - AMCC 3ware Installation Manual

Initializing Units
configurations use an optimized writing technique which does not
have to be valid to provide fault tolerance.
RAID 5 units with 5 or more disks, and RAID 50 units with 10 or
12 disks configured into two subunits do need to be initialized for
full performance. For these configurations, initialization begins
automatically after you create them in the 3BM utility. Zeroes are
written to all unit members.
If you want to use a RAID configuration which has started
initializing, press Esc to cancel the progress box. You can then exit
3BM and boot to the operating system before the process of writing
zeroes to the drives is complete. Once you have booted to the
operating system, initialization of the RAID 5 or RAID 50 unit will
begin after a delay of up to ten minutes.
When initializing is done after booting to the OS, the process of
initializing takes longer than it does if initialization is done by
writing zeroes to the array in the BIOS. Consequently, it will be a
longer period of time until the performance of the unit is fully
optimal.

For RAID 1 and RAID 10

RAID 1 and RAID 10 units are not initialized when they are created
and are immediately available for use with full performance when
created.
Initialization of RAID 1, RAID 10, RAID 5 with 3 or 4 disks,
RAID 50 with 6, 8, or 9 drives, and RAID 50 with 12 drives
configured in 3 subunits of 4 each or 4 subunits of 3 each will take
place the first time the array is verified, either via 3BM, through
3ware 3DM 2, or through the 3ware CLI. The steps below describe
how to do this through the BIOS (3BM). For information about
using 3DM 2, see 3ware 9000 Series Serial ATA RAID Controller
User Guide. For information about using the CLI, see 3ware
Escalade 9000 Series Serial ATA RAID Controller CLI Guide.
www.3ware.com 49