Adaptive Power Mode Tuning for QoS Guarantee in Cyber-Physical Systems

摘要

The Quality of Service (QoS) of Cyber-physical systems (CPS) is inevitably undermined by various physical uncertainties which include the stochastic environment noise and dynamics of the physical phenomenon. Both of those uncertainties might lead to task overload and the power overconsumption as task execution times are unpredictable. While recent feedback control scheduling have shown promise to meet the real-time requirement by adaptively adjusting the task loading rate, little work has focused on both the system service rate and the CPU execution modes as a whole to optimize the system QoS. This paper presents a feedback control based scheme that adaptively maintains desired task service rate for real-time requirement while minimizes the power consumption by assigning proper execution modes on processor for each node. The theoretic analysis, numerous simulations and experimentations demonstrate that the proposed scheme can provide robust real-time guarantees and reduce the power consumption when the task workload vary significantly at run-time.