Simultaneous optimization of battery-aware voltage regulator scheduling with dynamic voltage and frequency scaling

Energy-aware task scheduling significantly reduces the total energy required by a system to perform a particular job, by dynamically changing the clock frequency and supply voltage at which the CPU operates. But this causes significant fluctuation of the current drawn from the power source, so that no single voltage regulator can achieve satisfactory efficiency over the entire range of operating currents. We introduce a new method of high-level power management called dynamic voltage regulator scheduling (DRS), which overcomes the fundamental limitation of using a single voltage regulator. In a system equipped with DRS, heterogeneous voltage regulators are connected to a CPU through a multiplexer-type MOSFET switch. As the operating frequency and the supply voltage of the CPU vary, the most efficient voltage regulator is used to supply the power. We first describe a greedy method of achieving DRS, and then we progress to an integer linear programming (ILP) formulation, which simultaneously optimizes DRS together with dynamic voltage and frequency scaling (DVFS). We evaluate the performance of both greedy DRS and optimal DRS. Compared to conventional DVFS, greedy DRS saves an additional 5.4% to 14.6% of the total system energy; and optimal DRS saves an additional 11.5% to 15.5%.

[1]  Xiliang Zhong,et al.  System-wide energy minimization for real-time tasks: Lower bound and approximation , 2008, ACM Trans. Embed. Comput. Syst..

[2]  Chaitali Chakrabarti,et al.  Battery-conscious task sequencing for portable devices including voltage/clock scaling , 2002, DAC '02.

[3]  Massoud Pedram,et al.  Power-aware scheduling and dynamic voltage setting for tasks running on a hard real-time system , 2006, Asia and South Pacific Conference on Design Automation, 2006..

[4]  Youngsoo Shin,et al.  Power conscious fixed priority scheduling for hard real-time systems , 1999, Proceedings 1999 Design Automation Conference (Cat. No. 99CH36361).

[5]  Dongkun Shin,et al.  Intra-Task Voltage Scheduling for Low-Energy, Hard Real-Time Applications , 2001, IEEE Des. Test Comput..

[6]  Massoud Pedram,et al.  Design of an efficient power delivery network in an soc to enable dynamic power management , 2007, Proceedings of the 2007 international symposium on Low power electronics and design (ISLPED '07).

[7]  Taewhan Kim,et al.  DC–DC Converter-Aware Power Management for Low-Power Embedded Systems , 2007, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems.

[8]  Massoud Pedram,et al.  Design considerations for battery-powered electronics , 1999, Proceedings 1999 Design Automation Conference (Cat. No. 99CH36361).

[9]  F. Frances Yao,et al.  A scheduling model for reduced CPU energy , 1995, Proceedings of IEEE 36th Annual Foundations of Computer Science.

[10]  Russ Joseph,et al.  Power Deregulation: Eliminating off-chip voltage regulation circuitry from embedded systems , 2007, 2007 5th IEEE/ACM/IFIP International Conference on Hardware/Software Codesign and System Synthesis (CODES+ISSS).

[11]  Massoud Pedram,et al.  Optimal Selection of Voltage Regulator Modules in a Power Delivery Network , 2007, 2007 44th ACM/IEEE Design Automation Conference.

[12]  Naehyuck Chang,et al.  PVS: passive voltage scaling for wireless sensor networks , 2007, Proceedings of the 2007 international symposium on Low power electronics and design (ISLPED '07).

[13]  Hiroto Yasuura,et al.  Voltage scheduling problem for dynamically variable voltage processors , 1998, Proceedings. 1998 International Symposium on Low Power Electronics and Design (IEEE Cat. No.98TH8379).

[14]  Chaitali Chakrabarti,et al.  Extending the lifetime of fuel cell based hybrid systems , 2006, 2006 43rd ACM/IEEE Design Automation Conference.