Energy Consumption Reduction Techniques in Real-Time Embedded Systems

Abstract

Real-time embedded systems are incorporated in every detail of our contemporary life from simple gadgets to avionics complex systems. Power is one of the important criteria for optimization in the design and operation of real-time embedded systems. Mainly used techniques to reduce energy consumption in the processor unit are dynamic voltage/ frequency scaling (DVFS), based on processor slowdown capabilities, and dynamic power management (DPM). In this study, using resource access protocols and real-time scheduling algorithms; MaxSpeed (MS) and critical section maximum speed (CSMS) techniques of DVFS and DPM were examined with examples run on the MCRTsim simulation program to obtain and compare results. The obtained results showed that applying such techniques can reduce energy consumption to ratios of 27% for the utilized examples.

Keywords

• Real-time system
• Energy consumption
• DVFS
• DPM
• MCRTsim

Gerçek Zamanlı Gömülü Sistemlerde Enerji Tüketiminin Azaltılması için Teknikler

Abstract

Gerçek zamanlı gömülü sistemler, basit gadget'lardan karmaşık aviyonik sistemlere kadar modern hayatımızın her detayına dahil edilmiştir. Güç, gerçek zamanlı gömülü sistemlerin tasarımı ve işletiminde optimizasyon için önemli ölçütlerden biridir. İşlemci biriminde enerji tüketimini azaltmak için başlıca kullanılan teknikler; işlemcinin yavaşlama faktörlerine dayalı dinamik voltaj/frekans ölçeklendirmesi (DVFS) ve dinamik güç yönetimi (DPM)dir. Bu çalışmada kaynaklara erişim protokolleri ve gerçek zamanlı zamanlama algoritmaları kullanarak; DVFS içerisinde yer alan MaxSpeed (MS) ve kritik bölüm maksimum hız (CSMS) teknikleri, ve DPM incelenmiş ve yapılan örnekler MCRTsim programı üzerinde çalıştırılıp sonuçları alınıp karşılaştırılmıştır. Elde edilen sonuçlar, bu tekniklerin uygulanmasının, kullanılan örneklerde enerji tüketimini %27'ye kadar azaltabileceğini göstermiştir.

Keywords

• Gerçek zamanlı sistem
• Enerji tüketimi
• DVFS
• DPM
• MCRTsim

References

1. [1]Henrik Lipskoch, Karsten Albers, Frank Slomka, “Fast Calculation of Permissible Slowdown Factors for Hard Real-Time Systems”. Proceedings of the 17th international conference on Integrated Circuit and System Design: power and timing modeling, optimization and simulation (PATMOS'07), Sweden, pp.495-504, 2007.
2. [2] J. W. S. Liu, Real-Time Systems. Upper Saddle River, NJ: Prentice-Hall, 2000.
3. [3] Laplante PA, Ovaska SJ. Real-Time Systems Design and Analysis: Tools for the Practitioner. 4th ed. Hoboken, NJ: JOHN WILEY & SONS, 2012.
4. [4] Schmitz, M. T., Al-Hashimi, B. M., & Eles, P. (2005). System-level design techniques for energy-efficient embedded systems. System-Level Design Techniques for Energy-Efficient Embedded Systems (pp. 1–194). Springer US. https://doi.org/10.1007/b106642
5. [5] Padmanabhan Pillai and Kang G. Shin. 2001. Real-time dynamic voltage scaling for low-power embedded operating systems. SIGOPS Oper. Syst. Rev. 35, 5 (Dec. 2001), 89–102. DOI:https://doi.org/10.1145/502059.502044
6. [6] M. Awadalla, and A. Elewi. "Enhanced PSO approach for real time systems scheduling." International Journal of Computer Theory and Engineering 8.4 (2016): 285-289. https://doi.org/10.7763/ijcte.2016.v8.1059
7. [7] E. M. Saad, A. Elewi, M. Shalan and M. Awadalla, "Energy and synchronization-aware mapping of real-time tasks on asymmetric multicore platforms". International Journal of Computer Applications (IJCA), 75.11 (2013): 35-40. https://doi.org/10.5120/13159-0932
8. [8] Salih Palamut; Tuğba Gönültaş; Abdullah Elewi; Erdinç Avaroğlu, Task Scheduling Algorithms and Resource Access Protocols in Real Time Systems 2019 International Artificial Intelligence and Data Processing Symposium (IDAP), 2019.

9. [9] Yıldırım, M. K. , Süder, L. , Alkader, A. A. & Elewi, A. (2020). Çok İşlemcili Gerçek Zamanlı Sistemlerde Zamanlama Algoritmaları . Bilgisayar Bilimleri ve Teknolojileri Dergisi , 1 (2) , 42-50 . Retrieved from https://dergipark.org.tr/en/pub/bibted/issue/57253/788353
10. [10] Cheng, Albert MK, and James Ras. "The implementation of the priority ceiling protocol in Ada-2005." ACM SIGAda Ada Letters 27.1 (2007): 24-39.
11. [11] Baker, Theodore P. "Stack-based scheduling of realtime processes." Real-Time Systems 3.1 (1991): 67-99.
12. [12] Wu, J., ve Huang, Y. (2017). MCRTsim: A simulation tool for multi-core real-time systems. In 2017 International Conference on Applied System Innovation (ICASI), 461–464
13. [13] Jejurikar, Ravindra, and R. Gupta. "Energy aware edf scheduling with task synchronization for embedded real time systems." Proc. of the Workshop on Compilers and Operating Systems for Low Power. 2002.
14. [14] Jejurikar, Ravindra, and Rajesh Gupta. "Energy-aware task scheduling with task synchronization for embedded real-time systems." IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems 25.6 (2006): 1024-1037.
15. [15] Jejurikar, Ravindra, and R. Gupta. "Energy aware edf scheduling with task synchronization for embedded real time systems." Proc. of the Workshop on Compilers and Operating Systems for Low Power. 2002.
16. [16] L. Liu and J. W. Layland, “Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment,” J. ACM, 1973.
17. [17] Buttazzo, Giorgio C. Hard real-time computing systems: predictable scheduling algorithms and applications. Vol. 24. Springer Science & Business Media, 2011.
18. [18] Sha, L. & Goodenough, J., Real-time scheduling theory and Ada. IEEE Transactions on Computer, Vol. 23, No. 4, April 1990.