Building optimal applications against DB2 for z/OS is often difficult. As most of the real issues relate to maintenancence and changes in the surrounding parameters it’s necessary to define a methodology which enables performance monitoring as well as optimization in existing code.
By knowing more about how the SQL in your shop performs, a lot can be done to to anticipate future problems, such as identifying performance bottlenecks before they impact users and add to IT costs. By building a performance history table, where you monitor performance as time passes, and changes in the environment occur, it’s possible to be proactive, and optimize before the costs turns red.