Multiprocessor Frequency Locking for Real-Time Task Synchronization

Abstract

Energy-efficient real-time task scheduling is complicated by the deployment of co-processors. The problem complexity comes from the complexity in multiprocessor task scheduling and the difficulty in the trading of priority inversion with energy consumption. In this paper, a multiprocessor task synchronization protocol is proposed by locking the frequency of each (co-)processor and synchronizing resource sharing of tasks in a systematic way and with cross-(co)processor considerations. The well-known Priority Ceiling Protocol is taken as an example for its extension on energy-efficient real-time multiprocessor scheduling. The objective is to minimize the energy consumption of a task set and, at the same time, meet the task deadlines. The capability of the proposed methodology is evaluated by a series of experiments, for which encouraging results are presented.