Extending IOVF

The optional EXTEND_IOVF_#UOWS keyword allows the REORGANIZE command to extend the IOVF portion. When the IOVF increases by the specified number of UOWs, the SDEP CIs (if SDEP segments are defined and present), are moved to accommodate the increase.

To extend the IOVF during reorganization

1. Ensure that adequate space is present on the primary volume of the target area data set to accommodate the request before attempting to increase the IOVF portion during the reorganization function. If adequate space is not present, allocate additional volumes to the area data set by using IDCAMS ALTER ADDVOLUME.
2. Run the reorganization function by using the EXTEND_IOVF_#UOWS keyword to specify the number of UOWs to add.
3. When the reorganization function is complete, message BMC111193I is issued to the processing log, showing the new ROOT parameter for the DBD source. Use the values that are indicated in message BMC111193I to update the DBD definition to include the IOVF extension. Message BMC110000I is also issued, stating that the extension has been committed.

Sample control statements for extending IOVF

Sample control statements for extending IOVF during reorganization are shown in the following figure:

REORGANIZE   DBD=
dbdname, IAREA=
areaname,
  EXTEND_IOVF_#UOWS=50

Sample output

The following example shows messages BMC111193I and BMC110000I that are generated when adding50 UOWs to the IOVF portion:

BMC111193I<dbdname>, <areaname>: ROOT parameter changed from (200,100) to (250,150)

BMC110000I <dbdname>, <areaname>: AREA extensioncommitted <date>, <time>

When the database has been started for IMS, the following message, DFS3703I, is issued by IMS in the control region the first time that the area is opened:

DFS3703I Size of independent overflow has been increased for area <areaname>

Subsequent maintenance on the DEDB

The next time that you perform maintenance on the DEDB, you might need to change your area data set VSAM cluster definition to allow for the extended size of the SDEP portion.