IMS Catalog Database Space Analysis reference

The IMS Catalog Database Space Analysis report provides environmental and allocation information about the IMS catalog database. Allocation information is based on information obtained from the VTOC, such as extents and high used RBA.

You can view this report from the IMS Catalog Space and DBD/PSB Analysis panel.

This report contains the following information:

IMS Catalog Environment
The IMS Catalog Environment section displays the following information:
IMS ID
The IMS ID.
IMS version
The version of IMS.
Managed ACBs
  • ACBLIB: IMS management of ACBs is not enabled. ACBMGMT=ACBLIB is defined in the DFSDF member.
  • Catalog: IMS management of ACBs is enabled. ACBMGMT=CATALOG is defined in the DFSDF member.
DFSDF member
The DFSDFxxx member name in IMS PROCLIB.
Catalog DB Name
IMS catalog PHIDAM database name.
Partition Number
Number of PHIDAM partitions.
DB Org
Organization type of the data set.
IMS Catalog Database Space Usage
The IMS Catalog Database Space Usage section displays the following information:
Partition Name
PHIDAM partition name.
Grp
Data set group ID.
Data set name
The name of the data set.
Allocated extents
The number of allocated extents of the database data set.
IMS size limit
Maximum data set size that is limited by IMS.
Allocated space (Bytes)
Allocated space size of the database data set.
Used space (Bytes) (see Note)
Used space size that is high used RBA (Relative Bytes Address) of the database data set. It is the place of end-of-file.
IMS limit used (%) (see Note)
Ratio of used space to IMS space limit.
Allocated space used (%)
Ratio of used space to allocated space.
Note: Values displayed for used space and IMS limit used are derived from the data set high used RBA, which is the relative byte address of the end-of-file position. The end-of-file position does not change when instances are deleted from the IMS catalog; therefore, these values will not change even when instances are deleted from the IMS catalog. However, when instances are deleted from the space below the high used RBA, IMS can reuse the space as free space. To obtain the size of actual free space, use the HD Pointer Checker utility of IMS High Performance Pointer Checker or the FF Stand-alone Database Sensor.