A garbage collection performs several functions. It consolidates unused space in data sets, sets, and subsets and returns this space to the system. It can be used to reorder data sets to minimize access time. Finally, it can be used to generate a new set or automatic subset from an existing data set.

When using XE features, you can use the Visible DBS GARBAGE COLLECT command to initiate, terminate, and monitor the status of the online garbage collection of a set. For information about the GARBAGE COLLECT command, refer to the Enterprise Database Server Utilities Operations Guide.

To perform a garbage collection, run the Reorganization program. The garbage collection process does not involve any changes to the database description; therefore, it does not require recompilation of the DASDL description, the DMSUPPORT library, or user programs.