Performance Modeling in the Large: A Case Study

To manage complexity and to shorten design time, systemlevel methods for specification and design are becoming indispensable. System-level methods and tools focus on the creation of executable models that describe a system in the earliest phases of the design process. They allow qualitative (correctness) and quantitative (performance) properties to be analyzed before the system is actually being realized in terms of hardware and software components. The results of such early analysis can be used as input for taking well-founded design decisions. System-level methods and tools should be based on welldefined modeling languages to support developing an executable model that adequately represents the system to be designed. An example of such a modeling language is the Parallel Object-Oriented Specification Language (POOSL). POOSL enables to construct succinct executable models of complex real-time hardware/software systems. This paper describes our experiences with applying the POOSL formalism on analyzing the performance properties of an industrial-sized Internet Router system.