Serial Ata/Ide Raid; Introduction - CHAINTECH 7NJS Ultra User Manual

Serial ATA/IDE RAID

Introduction

What is the FastTrak 376 RAID controller?
Promise designed its FastTrak 376 to provide a cost-effective, high
performance RAID solution that adds performance and/or reliability to PC
desktops and/or servers using Serial ATA/150, Ultra ATA/133, Ultra ATA/100,
Ultra ATA/66, Ultra ATA/33 hard disks.
FastTrak 376 supports striping (RAID 0) or mirroring (RAID 1) for master
Device only.
RAID 0 (stripe)
For capacity -- The motherboard array will be as big as the smallest HDD in
the array times; however, many HDDs are in the array. Any larger HDDs will
simply be truncated. The truncated space on the bigger HDDs will then be
unusable.
For sustained data transfers -- A RAID 0 array consisting of two HDDs will
transfer at about twice the speed of the slowest HDD in the array. A RAID 0
array consisting of four HDDs will transfer at about three times the speed of the
slowest HDD in the array.
Reads and writes sectors of data interleaved between multiple drives. When
any disk member fails, it affects the entire array. Performance is better than a
single drive since the workload is balanced between the array members. This
array type is for high performance systems. Identical drives are recommended
for performance as well as data storage efficiency. The disk array data capacity is
equal to the number of drive members times the smallest member capacity. For
example, one 1GB and three 1.2GB drives will form a 4GB (4 x 1GB) disk array.
Stripe Size - a value can be set from 1KB to 1024KB sector size. The size can
directly affect performance.
RAID 1 (mirror)
For capacity – This Motherboard array will be as big as the smallest HDD in
the array. The larger HDD will simply be truncated. The truncated space on the
bigger HDD will then be unusable.
For sustained data transfers -- This motherboard array will write data at the
rate of the slowest HDD in the array. This motherboard array will read data at
twice the rate of the slowest HDD in the array.
Writes duplicate data on to a pair of drives while reads are performed in
parallel. ATA RAID 1 is fault tolerant because each drive of a mirrored pair is
installed on separate IDE channels. If one of the mirrored drives suffers a
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Serial ATA/IDE RAID