Listing the Contents of a Catalog

You can list catalog records using the access method services LISTCAT command, or the ISMF line operator CATLIST. CATLIST produces the same output as LISTCAT, but places the output in a data set that can be browsed.

You can use the LISTCAT output to monitor catalog data sets. The statistics and attributes listed can be used to help determine if you should reorganize, recreate, or otherwise alter a catalog data set to improve performance or avoid problems.

For example, you can use the values for High Used RBA and High Allocated RBA to help avoid out-of-space conditions for a data set or catalog. If the High Used RBA is less than the High Allocated RBA, then at least one control area split can occur without adding another secondary extent to the data set. Of course, you do not need to be concerned about secondary extents unless the volume is full or the data set already has a large number of them. If a data set has a large number of secondary extents, you might want to recreate the data set in a single extent.

Most information concerning non-catalog data sets is maintained in the VTOC.

The statistical information contained in the self-describing entries for a BCS is not correct. Catalog management does not maintain information about the statistical attributes of a BCS.

The cluster entry name for a BCS is 44 bytes of zeros. The name of the data component is the name you gave the catalog. The name of the index component is generated according to the regular catalog rules. The rules for catalog generated names are described in z/OS DFSMS Using Data Setsz/OS DFSMS Using Data Sets.