A tool for describing and evaluating hierarchical real-time bus scheduling policies

We present a tool suite for building, simulating, and analyzing the results of hierarchical tree-like structure descriptions of the scheduling policy for modules sharing a bus in real-time applications. These schedules can be based on a variety of factors including characteristics of messages and time slicing and are represented in a hierarchical tree-like structure that specifies multiple levels of arbitration. This structure can describe many popular arbitration schemes. Our simulator evaluates the specified scheduling structure on a set of message traces for a given bus. We illustrate our approach by applying it to two examples: the SAE automotive benchmark and Voice over IP (VoIP). Although this paper deals with just bus scheduling policies, the approach can be easily extended to other real-time scheduling problems.