A performance modeling "blending" approach for early life-cycle risk mitigation

In this paper we describe our first experiences of a performance modeling "blending" approach for early life-cycle risk mitigation in a large enterprise integration project. The goal was to use performance modeling to assist with defining the requirements for the system and to identify areas of architecture and technology risk which could be addressed in future phases of the project. We modified our Service Oriented Performance Modeling approach to enable useful models to be constructed by "blending" data from a variety of imprecise and incomplete information sources prior to the existence of concrete requirements or implementations. The approach iterated over two phases to ensure that deficiencies in method and information identified in the first phase were addressed in the second phase. Activities included scenario and workload modeling in phase 1, and software infrastructure, workload and "blended" modeling in phase 2. The resulting models enabled early exploration of critical assumptions and architectural alternatives. The results were enthusiastically received by the client and used by key decision makers and as inputs for future project phases. The "blending" approach to early life-cycle performance modeling raised the profile of architecture performance risk mitigation in the inception phase, so that performance is more likely be a feature of the subsequent development phases.