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Experimental Effectiveness Analysis of EDF-eCos for Real-Time computing in Small Unmanned Helicopter OFP

Nodir Kodirov, Doo-Hyun Kim, Jun-Yeong Kim, Chang-Joo Moon


In this paper we mainly address task scheduling in embedded systems, which has a direct relationship with the system efficiency and an indirect relationship with its execution stability. Timeliness execution of application will guarantee system stability. Our practical application is running on Embedded Configurable OS (eCos) Real-Time OS with x86-architecture based embedded board. Need for and suitability of the Earliest Deadline First (EDF) scheduling algorithm for our practical application will be illustrated. EDF implementation approach will be explained fully, accompanied with source code skeletons. Enhanced kernel performance based on less re-scheduling needed, higher CPU utilization allowance and finer timeliness qualities will be demonstrated. Lastly, applicability of our implementation and results for embedded application carrying Real-Time computing of Small Unmanned Helicopter’s Operational Flight Program will be illustrated.

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Modern Operating Systems, by Andrew S. Tanenbaum, Pearson Education, 2nd edition, pp. 132-152, pp.~ 473-475, 2001.

Embedded software development with eCos, Anthony J. Massa, Prentice Hall, 2002.

Liu, C. L.; Layland, J, Scheduling algorithms for multiprogramming in a hard real-time environment, Journal of the ACM, Vol 20, No 1, pp.~46-61, 1973.

Giorgio C. Buttazzo, Rate Monotonic vs. EDF: Judgment Day, Real-Time Systems, Vol 29, No 1, pp.~ 5-26, 2005.

Jansen, Pierre G. and Mullender, Sape J. and Havinga, Paul J.M. and Scholten, Hans, Lightweight EDF Scheduling with Deadline Inheritance, Internal Report, University of Twente Publications, 2003.

Doo-Hyun Kim, Nodir Kodirov, Chun-Hyon Chang, Jung-Guk Kim, HELISCOPE Project: Research Goal and Survey on Related Technologies, ISORC 2009–12th IEEE International Symposium on Object / Component / service-oriented Real-time distributed Computing, pp.~112-118. Tokyo, Japan, March 17-20, 2009.

Nodir Kodirov, Doo-Hyun Kim, A Design Strategy for Enhancing eCos with EDF for Disaster Response System, International conference on IT Promotion in Asia 2009 in conjunction with International Summit on Information and Communication Technologies, pp.~212-216. Tashkent, Uzbekistan, September 21-25, 2009.

eCos home page -

Albert Cheng, Real-Time Systems: Scheduling, Analysis, and Verification. John Wiley & Sons. ISBN: 0471-184063, pp. ~45-55, 2002.

Alan Burns, Andy J. Wellings and Fengxiang Zhang, Combining EDF and FP Scheduling Analysis and Implementation in Ada 2005, Lecture Notes In Computer Science; Vol. 5570, Springer-Verlag, ISBN:978-3-642-01923-4, pp.~ 119-133, 2009.

Robert I. Davis and Alan B, A Survey of Hard Real-Time Scheduling Algorithms and Schedulability Analysis Techniques for Multiprocessor Systems, Technical Report available at

Y-H Chao, S-S Lin, K-J Lin, Schedulability issues for EDZL scheduling on real-time multiprocessor systems, Information Processing Letters, Volume 107, Issue 5, pp.~ 158-164, 2008

S.K. Baruah., A. Burns, Sustainable Scheduling Analysis, In Proceedings of the IEEE Real-Time Systems Symposium, pp. ~159-168, 2006.

T.P. Baker, S.K. Baruah, Schedulability Analysis of global EDF, Real-Time Systems, 38: pp.~223-235, 2008.

M. Bertogna, M. Cirinei, G. Lipari, Improved schedulability analysis of EDF on multiprocessor platforms, In Proceedings of the 17th Euromicro

Conference on Real-Time Systems, pp.~209-218, 2005.



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