RAID 4 vs. RAID 5
With respect to availability, RAID 5 will provide the same amount of protection as RAID 4.
However, there is a caveat to this discussion, in that this assumes that everything remains equal in the comparison. There are storage arrays that are built to provide optimal performance for one type of RAID set over another, or can be tuned to provide better performance than usual for certain types of RAID sets. I would suggest consulting the storage array manufacturer in such a case.
Nevertheless, usually RAID 5 seems to be the most reasonable catch-all RAID scheme that provides the best compromise between performance and protection until either one or the other becomes more important.
18 Jun 2007