Analytical Performance Model for Futurebus+ Systems

We describe an analytical performance model for IEEE Futurebus+-based systems with emphasis on real-time applications. The performance model forms the basis of a design tool for Futurebus+ systems. With this design tool, the expected execution-time behavior of planned multiprocessor-based systems may be assessed. The performance model consists of two levels: The bus level model and the application level model. The proposed bus level models reeect the diierent arbitration protocols deened by the Futurebus+ Standard. The system designer only has to select one of the proposed bus level models that corresponds to the employed arbitration protocol of the Futurebus+. Conversely , he has to construct a separate application level model for each application that is supposed to run in the Futurebus+ environment with the proposed mod-eling tools. An algorithm for evaluating the two-level performance model is described. Finally, possible re-nements of the performance model are summarized.