An Efficient Power-Aware Scheduling Algorithm in Real Time System

Personal portable devices such as DMB (digital multimedia broadcasting)s, PMP (portable multimedia player)s and PDA (portable digital assistant)s require long battery life without reducing their performance. Power consumption is one of important factors in ubiquitous environments. To reduce the dynamic power consumption, many researches have been conducted on the dynamic voltage and frequency scaling (DVFS). DVFS can reduce the power consumption proportionally to the square of the supply voltage. But processor operation under the critical speed increases the leakage current. Larger leakage current increases the static power consumption. This paper proposes a new power-aware scheduling algorithm that reduces the static and dynamic power consumption to use frequency scaling between two discrete voltage levels and under the critical speed while meeting the deadline of given applications. The simulation and experimental implementation show that the proposed scheduling algorithm results in up to 25% energy gains over traditional DVFS algorithms with two task scheduling policies.