This Article 
 Bibliographic References 
 Add to: 
An Energy-Efficient Slack Distribution Technique for Multimode Distributed Real-Time Embedded Systems
July 2005 (vol. 16 no. 7)
pp. 650-662

Abstract—In multimode distributed systems, active task sets are assigned to their distributed components for realizing one or more functions. Many of these systems encounter runtime task variations at the input and across the system while processing their tasks in real time. Very few efforts have been made to address energy efficient scheduling in these types of distributed systems. In this paper, we propose an analytical model for energy efficient scheduling in distributed real-time embedded systems to handle time-varying task inputs. A new slack distribution scheme is introduced and adopted during the schedule of the task sets in the system. The slack distribution is made according to the service demand at the nodes which affects the energy consumption in the system. The active component at a node periodically determines the service rate and applies voltage scaling according to the dynamic traffic condition observed at various network nodes. The proposed approach uses a comprehensive traffic description function at nodes and provides adequate information about the worst-case traffic behavior anywhere in the distributed network, thereby enhancing the system power management capabilities. We evaluate the proposed technique using several benchmarks employing an event driven simulator and demonstrate its performance for multimode applications. Experimental results indicate significant energy savings in various examples and case studies.

[1] A. Raha, S. Kamat, and W. Zhao, “Admission Control for Hard Real-Time Connections in ATM LANs,” Proc. IEEE INFOCOM Conf., Mar. 1996.
[2] R.L. Cruz, “A Calculus for Network Delay,” IEEE Trans. Information Theory, vol. 37, no. 1, pp. 114-141, 1991.
[3] Y. Shin and K. Choi, “Power Conscious Fixed Priority Scheduling for Hard Real-Time Systems,” Proc. Design Automation Conf., pp. 134-139, 1999.
[4] Y. Shin, K. Choi, and T. Sakurai, “Power Optimization of Real-Time Embedded Systems on Variable Speed Processors,” Proc. Int'l Conf. Computer-Aided Design, pp. 365-368, 2000.
[5] G. Quan and X. Hu, “Energy Efficient Fixed Priority Scheduling for Real-Time Systems on Variable Voltage Processors,” Proc. Design Automation Conf., pp. 828-833, June 2001.
[6] P. Pillai and K.G. Shin, “Real-Time Dynamic Voltage Scaling for Low-Power Embedded Operating Systems,” Proc. ACM Symp. Operating Systems Principles, Oct. 2001.
[7] J. Luo and N.K. Jha, “Power-Conscious Joint Scheduling of Periodic Task Graphs and a Periodic Tasks in Distributed Real-Time Embedded Systems,” Proc. Int'l Conf. Computer Aided Design, pp. 357-364, Nov. 2000.
[8] G. Fohler, “Joint Scheduling of Distributed Complex Periodic and Hard Aperiodic Tasks in Statically Scheduled Systems,” Proc. 16th Real-Time Systems Symp., pp. 152-161, Dec. 1995.
[9] S. Kanhere, H. Sethu, and A. Parekh, “Fair and Efficient Packet Scheduling Using Elastic Round Robin,” IEEE Trans. Parallel and Distributed Systems, vol. 13, no. 3, Mar. 2002.
[10] I. Stojmenovic and X. Lin, “Power-Aware Localized Routing in Wireless Networks,” IEEE Trans. Parallel and Distributed Systems, vol. 12, no. 11, Nov. 2001.
[11] R. Mishra, N. Rastogi, D. Zhu, D. Mosse, and R. Melhem, “Energy Aware Scheduling for Distributed Real-Time Systems,” Proc. Int'l Parallel and Distributed Processing Symp., Apr. 2003.
[12] K. Lahiri, A. Raghunathan, and S. Dey, “Communication Architecture Based Power Management for Battery Efficient System Design,” Proc. Design Automation Conf., June 2002.
[13] A. Nandi and R. Marculescu, “System-Level Power/Performance Analysis for Embedded Systems Design,” Proc. Design Automation Conf., pp. 599-604, June 2001.
[14] D. Zhu, R. Melhem, and B. Childers, “Scheduling with Dynamic Voltage/Speed Adjustments Using Slack Reclamation in Multi-Processor Real-Time Systems,” Proc. Real-Time Systems Symp., 2001.
[15] J. Luo and N.K. Jha, “Static and Dynamic Variable Voltage Scheduling Algorithms for Real-Time Heterogeneous Distributed Embedded Systems,” Proc. Asia and South Pacific Design Automation Conf., Jan. 2002.
[16] J. Luo and N.K. Jha, “Power-Profile Driven Variable Voltage Scaling for Heterogeneous Distributed Real-Time Embedded Systems,” Proc. VLSI Design Conf., Jan. 2003.
[17] 298620.htm, 2004.
[18] C.M. Woodside and G. GMonforton, “Fast Allocation of Processes in Distributed and Parallel Systems,” Proc. IEEE Trans. Parallel and Distributed Systems, vol. 4, no. 2, pp. 164-174, Feb. 1993.

Index Terms:
Multimode, traffic descriptor, slack management, service rate, low-power.
Rabi N. Mahapatra, Wei Zhao, "An Energy-Efficient Slack Distribution Technique for Multimode Distributed Real-Time Embedded Systems," IEEE Transactions on Parallel and Distributed Systems, vol. 16, no. 7, pp. 650-662, July 2005, doi:10.1109/TPDS.2005.78
Usage of this product signifies your acceptance of the Terms of Use.