3PAR InForm® OS 2.3.1 CLI Administrator's Manual (320-200180 Rev B, February 2010)

16.2
Overview
3PAR InForm CLI Administrator’s Manual InForm OS Version 2.3.1
16.1 Overview
The InForm OS automatically creates a balanced system layout by mapping virtual volumes to
many logical disks, and creating logical disks from chunklets drawn from many physical disks.
The I/O for each volume is striped across many physical disks, increasing the throughput of the
volume. As the system grows and new applications are introduced, new storage usage patterns
can emerge and the system performance can degrade.
There are several tools you can use to tune your system for peak performance.
■ Optimize virtual volumes with the optional 3PAR Dynamic Optimization feature. The
Dynamic Optimization feature uses the
tunevv command.
■ Reclaim unused logical disk and Common Provisioning Group (CPG) space with the compact
CLI commands. Compact logical disks with the
compactld command and CPGs with the
compactcpg command.
■ Tune physical disks with the optional 3PAR System Tuner feature. The System Tuner feature
uses the
tunepd command.
For more information about optimizing your system, see the 3PAR InForm OS Concepts Guide.
16.2 Dynamic Optimization
3PAR Dynamic Optimization is an optional feature that allows you to improve the performance
of virtual volumes without interrupting access. Use this feature to avoid over provisioning for
peak system usage by optimizing the layout of your virtual volumes. Dynamic Optimization
enables you to change the layout of virtual volumes without interrupting access to the system.
This functionality promotes system optimization through improved use of all physical resources
present in the system at a given time. In addition, Dynamic Optimization enables you to alter
the service levels associated with a given volume by changing volume parameters. You must
have a 3PAR Dynamic Optimization license to use this feature and the
tunevv command.
For example, when an InServ Storage Server is upgraded by adding nodes, cages, or physical
disks, the initial volume and logical disk layouts may no longer be optimal for the new system
configuration. Dynamic Optimization enables you to change the layout of volumes and use
entirely new parameters to take advantage of the current system configuration.
There are four general cases where Dynamic Optimization may be desirable: