Figure 9-11. Shown is a highly abstracted response-time graph with minimal information. It is used to convey the performance situation as unacceptable and clearly in the elbow of the curve. People seem to intuitively know that being in the elbow of the curve is a bad thing.

If you feel it is necessary, then show the numbers. Be ready to explain them, how they relate to performance, and how your solutions will alter the situation.

Figure 9-12 was created using the same data as the graph in Figure 9-11. The only difference is that I included the numbers and used standard words (for example, "response time") and metrics (for example, "exec" for executions and "ms" for milliseconds). If asked why the SQL execution metric is relevant, I may respond that there is a CPU bottleneck, and in this system, the number of SQL statement executions directly impacts CPU consumption, which affects the response time. As I'll detail in later sections, you can also state that your proposed solutions are aimed at reducing the execution rate and the impact of each execution.