Optimizing performance analysis for synchronous dataflow graphs with shared resources

Contemporary embedded systems, which process streaming data such as signal, audio, or video data, are an increasingly important part of our lives. Shared resources (e.g. memories) help to reduce the chip area and power consumption of these systems, saving costs in high volume consumer products. Resource sharing, however, introduces new timing interdependencies between system components, which must be analyzed to verify that the initial timing requirements of the application domain are still met. Graphs with synchronous dataflow (SDF) semantics are frequently used to model these systems. In this paper, we present a method to integrate resource sharing into SDF graphs. Using these graphs and a throughput constraint, we will derive deadlines for resource accesses and the amount of memory required for an implementation. Then we derive the resource load directly from the SDF description, and perform a formal schedulability analysis to check if the original timing constraints are still met. Finally, we perform an evaluation of our approach using an image processing application and present our results.