Tuning the Database Reactively

This section lists and describes the steps required to tune the database based on user feedback. This tuning procedure is considered reactive. Perform this procedure periodically when performance problems are reported by the users.

To tune the database reactively: 

1. Run ADDM manually to diagnose current and historical database performance when performance problems are reported by the users, as described in Manual Database Performance Monitoring.

   This task is useful if you want to analyze current database performance before the next ADDM analysis, or to analyze historical database performance when you were not proactively monitoring the system.

2. Resolve transient performance problems, as described in Resolving Transient Performance Problems.

   The Active Session History (ASH) reports enable you to analyze transient performance problems with the database that are short-lived and do not appear in the ADDM analysis.

3. Resolve performance degradation over time, as described in Resolving Performance Degradation Over Time.

   The Automatic Workload Repository (AWR) Compare Periods report enables you to compare database performance between two periods of time, and resolve performance degradation that may happen from one time period to another.

4. Validate that the changes made have produced the desired effect, and verify that the users perceive performance improvements.

5. Repeat these steps until your performance goals are met or become impossible to achieve due to other constraints.