Elements of RAID 5 protection
This topic describes and illustrates RAID 5 protection.
The following diagrams illustrate the elements of a parity set that contains four disk units. Each parity set begins with an IOP that is attached to an IOA, which contains the write cache. The IOA transmits read and write signals to the attached disk units.
P indicates the sections of the disk that contain parity data.
Performance is improved by spreading the parity data throughout each of the disk units. The device parity protection that is spread throughout the disk units equals one disk unit of memory.