The
System Monitor (background) Process is responsible for database maintance. Its tasks include
- Instance recovery
- Dead transaction recoveryk
- Manage temporary tablespace metadata
- Reclaim lost space by orphaned temporary segments
- Adjust size of undo tablespaces by onlining, shrinking and offlining undo segments (based on undo space usage statistics)
- Clean up data dictionary
- Maintains the SCN to time mapping table used to support Oracle Flashback features
- Update
col_usage$
- In a RAC environment, SMON can perform instance recovery for failed instances.