I’ll like speak about the minimal configuration for AWR snapshots, it is very important configure it as good as possible to gather all the information after you can use this information to performance proposes and maybe others like planning backups, batch proccess…
Use the next query to see the current settings for AWR. Remember the defaults are 8 days of retention with samples each hour.
SELECT EXTRACT( DAY FROM SNAP_INTERVAL) *24*60+ EXTRACT( HOUR FROM SNAP_INTERVAL) *60+ EXTRACT( MINUTE FROM SNAP_INTERVAL ) “SNAPSHOT INTERVAL”, EXTRACT( DAY FROM RETENTION) *24*60+ EXTRACT( HOUR FROM RETENTION) *60+ EXTRACT( MINUTE FROM RETENTION ) “RETENTION INTERVAL” FROM DBA_HIST_WR_CONTROL;
If you want change the seettings, use the next procedure;
-- -- If you don't specific any parameter it uses the current value. -- BEGIN DBMS_WORKLOAD_REPOSITORY.MODIFY_SNAPSHOT_SETTINGS( RETENTION => 50000, -- IN MINUTES INTERVAL => 20); -- IN MINUTES END; /
HTH – Antonio NAVARRO