Reliability Aware Power Management for Dual-Processor Real-Time Embedded Systems

Primary-Backup (PB) model has been a widely used model for reliability in dual-processor real-time systems. In recent literature, there have been a few works focussing on minimizing energy consumption of periodic task sets executing on such systems. One of the major drawbacks of these works is that they ignore the effects of frequency-scaling on fault arrival rates. In this paper, we present a modified Primary-Backup model for dual-processor systems that aims to maintain the reliability when employing power management techniques to minimize the overall energy consumption. Furthermore, the proposed approach exploits the uncertainties in the execution time of real-time tasks to better predict the available slack for energy management. The proposed modified PB-based Reliability-Aware Power Management (RAPM) approach was tested with synthetic task sets on both homogeneous and heterogeneous dual-processor systems. Simulation results show that it can achieve up to 67 % savings in expected energy consumption for low utilization task sets and up to 32 % savings for high utilization task sets without any loss in reliability in heterogeneous dual-processor systems.