HP-UX System Administrator's Guide: Logical Volume Management (5900-3028, March 2013)

de Specifies the starting location of the destination physical extents within
a destination physical volume.
se1 [-se2] Defines the source physical extent range, provided along with source
physical volume.
Beginning with the September 2009 Update, pvmove additionally provides these options:
-a Moves data to achieve auto-rebalance of disk space usage within a volume
group. Supported for Version 2.x volume groups only. See “Moving Data for
Disk Space Balancing: Auto Re-balancing” (page 74).
-f pv_path Moves data from the specified physical path, pv_path, to remaining physical
volumes to achieve balance. Supported only with the -a option.
-s Provides a summary preview report of the data move, but does not actually move
data. Used only with the -a and -p options for a preview of data auto-rebalance.
See the pvmove(1M) manpage for details on all its options.
NOTE: The pvmove command is not an atomic operation; it moves data extent by extent. The
following might happen upon abnormal pvmove termination by a system crash or kill -9:
For Version 1.0 volume groups prior to the September 2009 Update, the volume group can be
left in an inconsistent configuration showing an additional pseudomirror copy for the extents being
moved. You can remove the extra mirror copy using the lvreduce command with the –m option
on each of the affected logical volumes; there is no need to specify a disk.
For version 1.0 with September 2009 Update or Version 2.0 volume groups: On abnormal
termination, the contiguous LV in question might have its extents laid out in a non-contiguous
manner. If so, it is recommended that you run lvdisplay -v to check if the allocation policy for
the LV is broken. If it is broken, then run the steps below to make contiguous the extents of this LV:
1. Change the allocation policy of this LV to default (see lvchange(1M)).
2. Move the extents such that all the physical extents of the logical volume are contiguous (see
pvmove(1M)).
3. Change the allocation policy back to contiguous (see lvchange(1M).)
Moving Data for Disk Space Balancing: Auto Re-balancing
Definition
In this section, “balancing” refers to maintaining the percentage of free and used space on each
involved physical volume equal to the total percentage of free and used space on all the physical
volumes that are selected in the balance operation; calculations are based upon the number of
physical extents. Auto re-balancing refers to the automatic movement of extents based on the
optimal number of extents calculated automatically for each logical volume on each physical volume
involved in the re-balance operation. Beginning with the September 2009 Update of HP-UX, you
can achieve automatic re-balancing on Version 2.x volume groups using the –a option of the
pvmove command.
Purpose
Balancing achieves better space utilization for existing storage, especially after physical volumes
have been recently added or deleted. Additionally, balancing can give better I/O performance
for the target logical volumes.
74 Administering LVM