On the Use of Greedy Shapers in Real-Time Embedded Systems

Traffic shaping is a well-known technique in the area of networking and is proven to reduce global buffer requirements and end-to-end delays in networked systems. Due to these properties, shapers also play an increasingly important role in the design of multiprocessor embedded systems that exhibit a considerable amount of on-chip traffic. Despite the growing importance of traffic shapping in this area, no methods exist for analyzing shapers in distributed embedded systems and for incorporating them into a system-level performance analysis. Until now it was not possible to determine the effect of shapers on end-to-end delay guarantees or buffer requirements in such systems. In this work, we present a method for analyzing greedy shapers, and we embed this analysis method into a well-established modular performance analysis framework for real-time embedded systems. The presented approach enables system-level performance analysis of complete systems with greedy shapers, and we prove its applicability by analyzing three case study systems.