With the key queuing theory calculations performed and the response-time graph created, we are nearly ready to move on to anticipating the performance improvement impact of our various solutions. However, before we get to that topic, it is important to understand the ways we can alter the users' experience.

When it comes to improving performance, the bottom line is to get out of the elbow of the curve. As I have mentioned, when presenting a response-time curve, even nontechnical audiences quickly grasp that being in the elbow is "bad" and being out of the elbow is "good." Use this intuitiveness to demonstrate-even at a very high level-your performance-improving strategies. This will build confidence in your solutions and also help more effectively rank them.

Tuning Oracle, the application, or the operating system effectively reduces its requirements. For example, instead of a SQL statement consuming 5 seconds of CPU, it now consumes only 2 seconds of CPU. Thinking about the basic utilization formula of requirements divided by capacity, if requirements decrease and capacity remains the same, then the utilization must decrease. The only way to increase the utilization once again is to increase the requirements. One way to do this is to increase the workload; that is, the arrival rate. So, through tuning, we have provided the basic performance-enhancing options of decreased response time, increased throughput, or some combination of both.