Reorganizing logical volumes

If you find that a volume was sufficiently fragmented to require reorganization, you can use the reorgvg command (or smitty reorgvg) to reorganize a logical volume and make it adhere to the stated policies.

This command will reorganize the placement of physical partitions within the volume group according to the logical volume characteristics. If logical volume names are specified with the command, highest priority is given to the first logical volume in the list. To use this command, the volume group must be varied on and have free partitions. The relocatable flag of each logical volume must be set to yes for the reorganization to take place, otherwise the logical volume is ignored.

By knowing the usage pattern of logical volumes, you can make better decisions governing the policies to set for each volume. Guidelines are:

• Allocate hot LVs to different PVs.
• Spread hot LV across multiple PVs.
• Place hottest LVs in center of PVs, except for LVs that have Mirror Write Consistency Check turned on.
• Place coldest LVs on Edges of PVs (except when accessed sequentially).
• Make LV contiguous.
• Define LV to maximum size that you will need.
• Place frequently used logical volumes close together.
• Place sequential files on the edge.