Compaq StorageWorks HSG60 ACS Solution Software V8.6 for Compaq Tru64 UNIX Installation and Configuration Guide

Planning Storage 2–17
■ A RAIDset must include at least 3 disk drives, but no more than 14.
■ A storageset should only contain disk drives of the same capacity. The controller
limits the capacity of each member to the capacity of the smallest member in the
storageset. Thus, if you combine 9 GB disk drives with 4 GB disk drives in the
same storageset, you will waste 5 GB of capacity on each 9 GB member.
■ RAIDsets are particularly well-suited for the following:
❏ Small to medium I/O requests
❏ Applications requiring high availability
❏ High read request rates
❏ Inquiry-type transaction processing
■ RAIDsets are not particularly well-suited for the following:
❏ Write-intensive applications
❏ Database applications in which fields are continually updated
❏ Transaction processing
Striped Mirrorset Planning Considerations
Striped mirrorsets (RAID 0+1) are a configuration of stripesets whose members are
also mirrorsets (Figure 2–12). Consequently, this kind of storageset combines the
performance of striping with the reliability of mirroring. The result is a storageset with
very high I/O performance and high data availability. Figure 2–13 shows a second
example of a striped mirrorset using six members.