Dynamic runtime re-scheduling allowing multiple implementations of a task for platform-based designs

This paper introduces an extension to the RMS scheduling technique that we call "hot swapping". Hot swapping enables a system to choose between various selected implementations of one task on-the-fly and thus to optimize the system's cost (e.g. power savings). The on-the-fly swapping between those implementations requires extra time to save and/or transform states of a certain task implementation. Even if the two steady-state schedules before and after the swapping are feasible, the transient schedule with the additional swapping computation time may exceed the system's capacity. Our technique is an extension to rate monotonic scheduling (RMS). While maintaining and meeting performance requirements, our technique shows an average reduction of 31% in power consumption compared to systems using a pure static scheduling approach (RMS) that cannot make use of task swapping. We have evaluated our algorithm through simulation of five real-world task sets and in addition by use of a large number of generated task sets