Adaptive and Aggressive Low Power Load Balancing for Multicore Systems

Modern embedded systems commonly adopt a multi-core processor to provide high performance. In a multi-core processor, the operating system scheduler is in charge of migrating tasks across the multiple cores to maximize the resource utilization while minimizing the power consumption. In order to reduce power consumption further, the operating system scheduler often provides a power-saving mode which can be triggered according to some predetermined threshold value. However, it turns out that the statically fixed threshold is set to a low value which hardly triggers the power-saving mode. In this paper, we propose an adaptive and aggressive low power load balancer which makes cores enter a power-saving mode more frequently based on system condition. The proposed load balancer adjusts the threshold value for the power-saving mode taking some load balancing overhead into account. Experimental results show that the proposed load balancer enters the power-saving mode frequently to reduce power consumption by 6.81 % compared to a conventional load balancer