Provided that the Oracle system parameter CONTROL_MANAGEMENT_PACK_ACCESS is set at least to DIAGNOSTIC, Oracle will take performance snapshots at each hour. The ora_awr_addm script will create each night a report for the day from 08:00 to 17:00 as defined in the oracle_tools.conf. The resulting report is sent to ULS. No report can be produced if the database instance was bounced within the report time range.
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