I hope you found this course on RDS performance insights interesting, informative, and practical. I especially hope that you're motivated to continue learning about RDS performance monitoring and we'll apply what you've learned to your own particular challenges and needs inside the AWS cloud.

There were a number of topics in this course. Performance insights can help identify performance bottlenecks on an Amazon RDS instance. And if a problem is within the database located source. It's a fully automated feature of Amazon RDS where the impact of database performance limited to 1% of a CPU core. It is a graphical dashboard that has been designed to be easy to use by both novice and expert users.

Storage collection and the dashboard display is done automatically. Load is measured using a metric called average active sessions or AAS. AAS is calculated by sampling memory to determine the state of each active database connection. 

The sample data includes the SQL query, the state of the query, the host that originated the query, and the user running it. Active sessions are sampled once per second to present a seamless picture of a database's load. Performance insights metric data is stored, processed, and managed using AWS resources outside of the RDS instance. Since metric data is stored externally from RDS, analysis has no impact on database performance.

The performance insights dashboard shows as a default view, one hour of activity. It can be adjusted to show other timeframes. It is possible to view single-second data points by interacting with the graph.

When troubleshooting, performance insights can be used to eliminate the database as being a problem. If there's a database issue, performance insights can help identify the source and pinpoint the cause of the problem. The dashboard has four categories that identify contributions to database load, SQL, hosts, users, and waits. The default is to show the top SQL queries. However, it is possible to view the top hosts, top users, or top waits.

Access to performance insights can be granted and restricted using an IAM policy. There is a free tier that includes seven days of performance data and 1 million API calls. Once the free tier has been used, costs are based on consumption. Longterm retention of performance insights data is possible for up to two years.

Costs are calculated based on AWS region, number of CPU cores, and the number of hours the data is retained. When I was a child, my father would often take me to task for leaving lights on after I left a room, or forgetting to close the door when I went outside. His advice then translates to my advice now. Inside the AWS cloud, if you're not using it, turn it off. No sense in paying for something nobody's using. Likewise, if you leave a door open, someone or something will come in uninvited, that's never good and it will not end well.

If you're looking at AWS certification, performance insights might show up on the database specialty exam. You should know what performance insights measures, and how it is different from Amazon CloudWatch and RDS enhanced monitoring. It will also help you to know how to use CloudWatch, enhanced monitoring, and performance insights together to troubleshoot issues with Amazon RDS.

This brings me to the end of this lecture and the end of the course. Thank you for being part of it. If you have any feedback, positive or negative, please contact us at support@cloudacademy.com. It's greatly appreciated. We use your feedback to update existing content and to shape future courses.

Thank you again for watching and good luck with your continued learning of cloud computing.