Reclaiming Unmapped Logical Disk Space From Volumes; Automatically Reclaiming Unused Snapshot Space From Volumes; Manually Reclaiming Unused Snapshot Space From Volumes; Deleted Volume Snapshot Space - HP 3PAR StoreServ 7200 2-node Manual

with both the HP 3PAR Command Line Interface (CLI) and the HP 3PAR Management Console.
Refer to the HP 3PAR Command Line Interface Administrator's Manual and the HP 3PAR
Management Console Online Help for instructions on how to perform this task.

Reclaiming Unmapped Logical Disk Space from Volumes

When multiple identical virtual volumes are created as a result of a single volume creation operation,
the underlying logical disks that support those volumes are shared by the volume group. If several
of the members of that volume group are later deleted, the underlying logical disks may become
less efficient in the usage of space. One or more logical disks shared by the volume group may
have only a small portion of their regions mapped to existing virtual volumes. However, their
unused regions are not available to the system for use in creating new logical disks. Compacting
the logical disk regions mapped to these volumes may recover and free logical disk space.
Compacting logical disks can only be performed with the HP 3PAR Command Line Interface (CLI).
Refer to the HP 3PAR Command Line Interface Administrator's Manual for instructions on how to
perform this tasks.
You can use the optional HP 3PAR Dynamic Optimization Software feature to configure volumes
to use space more efficiently. To learn about tuning volumes for optimal performance, see
Storage Applications" (page

Automatically Reclaiming Unused Snapshot Space from Volumes

The HP 3PAR OS automatically reclaims unused snapshot and administration space from
Thinly-Provisioned Virtual Volumes (TPVVs) and fully-provisioned virtual volumes and returns the
space to the LDs. The system examines the snapshot and administration space for large areas of
unused space. The identified areas are unmapped from the corresponding LD regions and the
space is returned to the LDs.

Manually Reclaiming Unused Snapshot Space from Volumes

You cannot manually remove snapshot and administration space from a Thinly-Provisioned Virtual
Volume because the HP 3PAR OS automatically removes any unused space.
Reclaiming dormant snapshot and administration space from a fully-provisioned virtual volume and
returning the space to the LD can only be performed when the volume is not exported to a host,
and if there are no snapshots of the volume. Creating physical copies of the volume does not
prevent you from reclaiming space.
You can reclaim snapshot space from a virtual volume with both the HP 3PAR Command Line
Interface (CLI) and the HP 3PAR Management Console. Refer to the HP 3PAR Command Line
Interface Administrator's Manual and the HP 3PAR Management Console Online Help for instructions
on how to perform this task.

Deleted Volume Snapshot Space

The unused space associated with deleted snapshots of Thinly-Provisioned Virtual Volumes (TPVVs)
and fully-provisioned virtual volumes is automatically returned to the pool of logical disks used by
the CPG.

Logical Disks and Chunklet Initialization

After deleting Logical Disks, the underlying chunklets must be initialized before their space is
available to build LDs. The initialization process for chunklets generally takes about one minute
per 1GB chunklet and 20 seconds per 256MB chunklet. To see chunklets that are currently in the
process of being initialized, issue the showpd
listed in the Uninit column.
52 Reclaiming Unused Space
53).
c command. Chunklets that are uninitialized are
"Enhanced