Oracle Database 12c: Advanced Administration — Question 132

You notice that the performance of your production 24/7 Oracle 12c database has significantly degraded. Sometimes you are not able to connect to the instance because it hangs. You do not want to restart the database instance.
How can you detect the cause of the degraded performance?

Answer options

• A. Enable Memory Access Mode, which reads performance data from SGA.
• B. Use emergency monitoring to fetch data directly from SGA for analysis.
• C. Run Automatic Database Diagnostic Monitor (ADDM) to fetch information from the latest Automatic Workload Repository (AWR) snapshots.
• D. Use Active Session History (ASH) data and hang analysis in regular performance monitoring.
• E. Run ADDM in diagnostic mode.

Correct answer: C

Explanation

The correct answer is C, as running ADDM allows you to analyze the performance issues by utilizing the latest AWR snapshots, which provide a detailed view of the database's performance over time. Options A and B are less effective because they do not utilize comprehensive historical data. Option D focuses on ASH data, which is useful but not as holistic as ADDM in this context. Option E is incorrect as it implies a different mode of operation that may not offer the same insights as the standard ADDM process.