Temperature-Constrained Feasibility Analysis for Multicore Scheduling

Multicore platforms are becoming the primary choice to achieve high performance in today's embedded system design. However, under the current IC technology, the dramatic increase in power density has made the thermal issue a critical concern in design of multicore systems. In this paper, we study the problem on how to determine if a periodic dynamic voltage and frequency scaling (DVFS) schedule for a multicore platform is thermally feasible in satisfying a given peak temperature constraint. To solve this problem, we first develop a novel analytic method to quickly calculate the temperature at an arbitrary time instant, which can achieve orders-of-magnitude speedups over the HotSpot simulator. We then present an approach to pinpoint the peak temperature of a given periodic multicore DVFS schedule. Finally, we develop three methods to check the thermal feasibility of an arbitrary schedule. We formally prove the fundamental principles and validity of our proposed methods and use simulation results to demonstrate their effectiveness.