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Automatic workload repository (AWR)

AWR looks periodically at the system performance (by default every 60 minutes) and stores the information found (by default up to 7 days). This allows to retrieve information about workload changes and database usage patterns.
This information is the basis for all self-management decisions. For example, it is thus possible to identify the SQL statements that have the
  • larges CPU consumption
  • most buffer gets
  • disk reads
  • most parse calls
  • shared memory
The data is fed from MMON.
The information is stored in the sysaux tablespace.