Automatic volume and automatic secondary space management prepare the computing system for the addition of new data by freeing space on the DFSMShsm-managed volumes and DFSMShsm-owned volumes. Automatic volume space management includes automatic primary space management, interval migration, and on-demand migration.

During automatic primary space management, DFSMShsm performs space management on each requested DFSMShsm-managed volume at a specified time of day.

During interval migration, DFSMShsm ensures on an hourly basis that a specified amount of space is available on DFSMShsm-managed volumes.

During on-demand migration, DFSMShsm performs space management on eligible SMS-managed volumes immediately after the volume exceeds its high threshold.

During automatic secondary space management, DFSMShsm performs space management on eligible migrated data sets.