System Guidelines For Creating Common Provisioning Groups; Common Provisioning Group Cli Commands - HP 3PAR StoreServ 7200 2-node Administrator's Manual

There are several courses of action you can take such as adding physical disks to the system, or
limiting the future growth of volumes that draw from the CPG. Your response can vary, depending
on several factors:
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.
CAUTION:
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, either any new writes to TPVVs
associated with the CPG will fail, or snapshot volumes associated with the CPG may become
invalid, or both. Invalid volumes do not handle write failures gracefully and may produce unexpected
failures.
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 limits are set to none, which effectively
disables these safety features.
See the HP 3PAR Messages and Operator's Guide for additional information about specific alerts.
Managing alerts is described in

System Guidelines for Creating Common Provisioning Groups

When you use the advanced parameters for LD creation, use the following guidelines to ensure
maximum performance and optimal reliability in the volumes supported by those LDs:
Chunklets in the same RAID set should be from different drive magazines or drive cages.
Chunklets in the same row should be from different physical disks. In other words, a physical
disk should not appear twice in the same row.
Chunklets should belong to a disk that is connected through the primary path to the LD's owner
node.
The growth increment is limited to 40 chunklets.
The system should use as many physical disks as possible.
The load on all physical disks should be balanced.
The system should use the largest possible row size.

Common Provisioning Group CLI Commands

Use the following CLI commands to manage CPGs:
showcpg—display CPGs in the system.
createcpg—create CPGs.
setcpg—modify existing CPGs
compactcpg—consolidate LD space in CPGs into as few LDs as possible.
removecpg—remove CPGs from the system or remove specific LDs from CPGs.
Use caution in planning CPGs. The system does not prevent you from setting growth
"Managing Events and Alerts" (page 118).
Common Provisioning Group CLI Commands 79