Very high Read data transaction rateLow ratio of ECC (Parity) disks to data disks means high efficiencyHigh aggregate Read transfer rateLow ratio of ECC (Parity) disks to data disks means high efficiency
Quite complex controller designWorst Write transaction rate and Write aggregate transfer rateDifficult and inefficient data rebuild in the event of disk failureBlock Read transfer rate equal to that of a single diskEach entire block is written onto a data disk. Parity for same rank blocks is generated on Writes, recorded on the parity disk and checked on Reads. RAID Level 4 requires a minimum of 3 drives to implement.
