HP SureStore E Disk Array XP512/XP48 Owner's Guide

RAID Technology 101
Figure 16. RAID5 with Parity Disk
The downside to RAID0/1 over RAID5 is that there is a 100% overhead on
storage redundancy associated with RAID0/1. RAID0/1 is often referred to
as mirrored storage, because the user data is physically duplicated in the
array.
P (10-12) D11D10 D12
P (7-9) D7D9 D8
P (4-6)
D6
D5 D4
3D + 1P Array Group
P (1-3) D1 D2 D3