Figure 2-1. Simple instrumentation example. Each product's modules have a simple start and stop timer, providing the ability to determine the module run time.

The development manager then repeatedly ran the product while the timers were recording module start and stop times. After he was satisfied that enough runs had occurred, he ran the query shown in Figure 2-2, and got the results shown in that figure.

Figure 2-2. Sample instrumentation analysis code and the actual results. After repeated product runs, module C clearly took the most time.