VERITAS Volume Manager 3.1 Administrator's Guide

Performance Monitoring

Performance Guidelines:

Chapter 9394

decrease of effective disk space utilization. Performance can also be

improved by striping across half of the available disks to form one plex

and across the other half to form another plex. When feasible, this is

usually the best way to conﬁgure the Volume Manager on a set of disks

for best performance with reasonable reliability.

Mirroring and Striping

NOTE You may need an additional license to use this feature.

When used together, mirroring and striping provide the advantages of

both spreading data across multiple disks and providing redundancy of

data.

Mirroring and striping can be used together to achieve a signiﬁcant

improvement in performance when there are multiple I/O streams.

Striping can improve serial access when I/O exactly ﬁts across all stripe

units in one stripe. Better throughput is achieved because parallel I/O

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.

Striping and Mirroring