3PAR InForm® OS 2.2.4 CLI Administrator's Manual (320-200113 Rev A, March 2009)

7.11
Common Provisioning Groups
InForm OS Version 2.2.4 3PAR InForm OS CLI Administrator’s Manual
You can create two types of base volumes that draw from the CPG's logical disk pool: Thinly
Provisioned Virtual Volumes (TPVVs) and Commonly Provisioned Virtual Volumes (CPVVs).
These two volume types draw from the pool in different ways. For information on TPVVs and
CPVVs, refer to the 3PAR InForm Concepts Guide.
7.10.1 Growth Increment Considerations
The default growth increment of a CPG is fixed at 32 GB, but the minimum growth increment
varies according to the number of controller nodes in the system and ranges from 8 GB for a
two-node system to 32 GB for a four-node system (Table 7-1).
Table 7-1. Default and Minimum Growth Increments
Number of nodes Default Minimum
2 32 GB 8 GB
4 64 GB 16 GB
6 96 GB 24 GB
8 128 GB 32 GB
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 (stale).
Under this condition, some host applications 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. Doing so can invalidate snapshot volumes.