Nvidia 754 User Manual

Nvidia 754 User Manual Manual pdf 56 page image

RAID ConfigurationPage 5-2RAID 0 (Striping)RAID 0 reads and writes sectors of data interleaved between multiple drives. If anydisk member fails, it affects the entire array. The disk array data capacity is equal to thenumber of drive members times the capacity of the smallest member. The stripingblock size can be set from 4KB to 64KB. RAID 0 does not support fault tolerance.RAID 1 (Mirroring)RAID 1 writes duplicate data onto a pair of drives and reads both sets of data inparallel. If one of the mirrored drives suffers a mechanical failure or does notrespond, the remaining drive will continue to function. Due to redundancy, thedrive capacity of the array is the capacity of the smallest drive. Under a RAID 1setup, an extra drive called the “spare drive” can be attached. Such a drive will beactivated to replace a failed drive that is part of a mirrored array. Due to the faulttolerance, if any RAID 1 drive fails, data access will not be affected as long as thereare other working drives in the array.JBOD (Spanning)A spanning disk array is equal to the sum of the all drives when the drives used arehaving different capacities. Spanning stores data onto a drive until it is full, thenproceeds to store files onto the next drive in the array. When any disk memberfails, the failure affects the entire array. JBOD is not really a RAID and does notsupport fault tolerance.OthersOther RAID derivatives are RAID 10 and RAID 5. These RAID levels require morethan 2 drives to operate, combining the benefits of RAID 0 and RAID 1.