VERITAS Volume Manager 3.1 Administrator's Guide

Performance Monitoring
Performance Guidelines:
Chapter 9 395
streams can operate concurrently on separate devices.
Since mirroring is most often used to protect against loss of data due to
disk failures, it may sometimes be necessary to use mirroring for
write-intensive workloads. In these instances, mirroring can be
combined with striping to deliver both high availability and
performance. See “Layered Volumes”.
Using RAID-5
NOTE You may need an additional license to use this feature.
RAID-5 offers many of the advantages of using mirroring and striping
together, but RAID-5 requires less disk space. RAID-5 read performance
is similar to that of striping and RAID-5 parity offers redundancy similar
to mirroring. Disadvantages of RAID-5 include relatively slow writes.
RAID-5 is not generally seen as a performance improvement mechanism
except in cases of high read-to-write ratios shown in the access patterns
of the application.