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

7.5
Common Provisioning Groups
InForm OS Version 2.3.1 3PAR InForm CLI Administrator’s Manual
■ Total available space on your system.
■ Nature of the data running on the system.
■ Number of CPGs in the system.
■ Number of volumes associated with those CPGs.
■ Anticipated growth rate of the volumes associated with the CPGs.
7.2.2 System Guidelines for Creating Common Provisioning Groups
When you use the advanced parameters for logical disk creation, use the following guidelines
to ensure maximum performance and optimal reliability in the volumes supported by those
logical disks:
■ Chunklets in the same RAID set should be from different drive magazines or drive cages.
CAUTION: Use caution in planning CPGs. The system does not prevent you from
setting growth warnings or growth limits that exceed the amount of currently
available storage on a system. When volumes associated with a CPG use all space
available to that CPG, any new writes to TPVVs associated with the CPG will fail
and/or snapshot volumes associated with the CPG may become invalid. Invalid
volumes do not handle write failures gracefully and may produce unexpected
failures.
CAUTION: Do not allow volumes that draw from a CPG to exceed the CPG's
growth limit. Exceeding the CPG growth limit can invalidate snapshot volumes.
NOTE: By default, the growth warning and growth limit are set to none, which
effectively disables these safety features.
NOTE: Refer to the InForm OS Messages and Operator’s Guide for additional
information about specific alerts. Managing alerts is described in Chapter 11,
Managing Events and Alerts.