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1. In the Instance list, choose the instance you want to analyze.
   Do one of the following:
   • On the View controls in the Main area, click Overview. This will show you a breakdown of resource consumption for the last minute.
   • On the View controls, click Statistics to analyze the current statistics of the selected instance.
2. In the Main area, check for any unproductive wait states. In our example, the sessions on average (in the % column) are spending roughly a third of their time (34.91%) waiting on the redo log buffer.
3. To further investigate, launch the Statistics tab. View the Statistics tab to look for system events that relate to the redo log buffer. Launch to the Statistics tab, in context, to view additional statistical information for any selected instance.
4. In the Association area, move the cursor over the In Oracle bar in the list of Active Sessions to display a ToolTip that shows which sessions are spending the majority of their time waiting on Redo Log Buffer Wait.
5. Check how much time is spent using CPU. If all other wait states have been eliminated, obviously this will be 100%; therefore, it is important to look at the actual time (in hh:mm:ss), in the Main area, as well as the percentage value. High CPU usage can indicate excessive logical I/O operations.
6. To further investigate, open the Activity tab. Try tuning any SQL with a high Using CPU time and high values for the statistics consistent gets and db block gets.

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