Table 9-5 shows how to set up a batch process analysis. The entire batch process has been segmented into three steps, or segments. Step determination is based on your objectives, available statistics, and your audience. The time data comes from the same sources as with online transactions, but, as you'll see, with a slight yet significant twist. When the process steps have been defined and the respective data collected, a table similar to Table 9-5 can be constructed.

In addition to helping focus the analysis, a setup similar to Table 9-5 naturally allows us to calculate anticipated change with a greater degree of accuracy. For example, if we believe through increased parallelism the Load step's write time can be reduced by 50%, we can easily adjust the table and recalculate the response time. So not only does this table help us understand the situation, target our efforts, and communicate the situation to others, it also aids in anticipating performance improvements.

To help understand the complexity of working on each step, additional columns can be helpful. For example, the table could also include the number of top SQL statements and some complexity metric. The point is that the table should encourage fruitful discussion and analysis, so an informed decision can be made about where to target the performance effort.