Yuan Yao, An Oracle ACE's Blog

When investigating a database performance issue, you don’t need to go through the full AWR report line by line, you only need to read from the beginning of the report up to the Time Model Statistics section.

This range includes the report header and the Report Summary section.

Although these parts only make up a small portion of the full report, they contain the key information you need to understand the database’s overall performance from a macro perspective.

By analyzing these parts, you can answer two fundamental questions:

• Where are user sessions spending time? (from user’s perspective)
• How is Oracle consuming resources? (from database’s perspective)

Once you’ve answered these two questions, you’ll know which remaining sections require deeper investigation.

This enables you to skip over the “healthy” parts and focus your attention on areas that show real anomalies.

In most performance cases, the SQL Statistics section is a must-read, since many performance issues originate from inefficient SQL statements.

I’ll go into more detail about this analysis approach in later articles.