Disk Array Terms - Gigabyte Promise RAID Function User Manual

RAID Function

6-5 Disk Array Terms

Disk Array Description
A "disk array" is formed from a group of 2 or more disk drives which appear to the
system as a single drive. The advantage of an array is to provide better throughput
performance and/or data fault tolerance. Better performance is accomplished by sharing
the workload in parallel among multiple physical drives. Fault tolerance is achieved
through data redundant operation where if one (or more) drive fails or has a sector
failure, a mirrored copy of the data can be found on another drive(s).
For optimal results, select identical Ultra ATA/133 drives to install in disk arrays. The
drives' matched performance allows the array to function better as a single drive.
Disk Array Member
The individual disk drives in an array are called "members." Each member of a specific
disk array is coded in their "reserved sector" with configuration information that
identifies the drive as a member. All disk members in a formed disk array are recognized
as a single physical drive to the system.
Disk Array Types
For most installations, the FastBuild TM setup "<1> Auto Setup" option will config-
ure your system.
There are two disk array types in three categories that can be installed on the
RAID Function . Striping is in the Performance category while Mirroring,
Striping/Mirroring are in the Fault Tolerance category.
Disk arrays within the Performance and Fault Tolerance categories conform with the
Redundant Array of Independent Disks technology, or RAID. The RAID levels
supported are 0 and 1.
RAID Level
RAID 0 (Striping)
RAID 1 (Mirroring)
Performance
Highest # Drives x Smallest Size
Normal
5 0
Capacity
50% min
# of
Drives
2
2