I/O-Aware List Scheduling for Distributed Embedded Systems

This paper discusses list scheduling for distributed real-time embedded systems. The goal is to provide more realistic scheduling, taking into account the actual distribution of sensors and actuators in different locations of the controlled object. We propose an I/O-aware DFG as a suitable replacement for the general DFG. Along with the locations of the peripherals, the bus activity is another issue which is usually ignored. We calculate bus activities to assess the power efficiency of the scheduling. The proposed I/O-driven scheduling is a simplified procedure for rapid evaluation of the timing parameters which emerge after scheduling. Finally, we discuss I/O-aware scheduling as a modification of the list scheduling heuristic. The I/O-aware scheduling takes into account the computation and communication for both intertask and task-to-peripheral links.