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Effective Analysis for Engineering Real-Time Fixed Priority Schedulers
May 1995 (vol. 21 no. 5)
pp. 475-480
There has been considerable activity in recent years in developing analytical techniques for hard real-time systems. Inevitably these techniques make simplifying assumptions so as to reduce the complexity of the problem to be solved. Unfortunately this leads to a gap between theory and engineering practice. This paper presents new analysis that enables the costs of the scheduler (clock overheads, queue manipulations and release delays) to be factored into the standard equations for calculating worst-case response times. As well as predicting the true behavior of realistic systems, the analysis also allows free parameters, such as clock interrupt rate, to be determined.

[1] N. Audsley,A. Burns,R. Davis,K. Tindell,, and A. Wellings,“Fixed priority scheduling: An historical perspective,” Real-Time Systems, vol. 8, no. 2/3, pp. 129-154, Mar. 1995.
[2] A. Burns,”, “Preemptive priority based scheduling: An appropriateengineering approach,” in Advances in Real-Time Systems, S.H. Son, ed. Prentice Hall, pp. 225-248, 1993.
[3] D.I. Katcher, H. Arakawa, and J.K. Strosnider, “Engineering and Analysis of Fixed Priority Schedulers,” IEEE Trans. Software Eng., vol. 19, no. 9, pp. 920–934, Sept. 1993.
[4] C. Bailey, E. Fyfe, T. Vardanega, and A. Wellings,“The use of preemptive priority-based scheduling for spaceapplications,” Proc. Real-Time Systems Symp., pp. 253-257, Dec. 1993.
[5] A. Burns,A. Wellings,C. Bailey,, and E. Fyfe,The Olympus Attitude and Orbital Control System: A Case Study in HardReal-Time System Design and Implementation,” Dept. of Computer Science, Univ. of York, England, 1993.
[6] York Software Engineering Ltd., York Ada Compiler Environment (York ACE) Reference Guide, 1991.
[7] Intermetrics, Inc., Ada 9X Reference Manual. Draft. Ver. 5.99, Dec. 1994.
[8] C.D. Locke, D.R. Vogel, and T.J. Mesler, “Building a Predictable Avionics Platform in Ada: A Case Study,” Proc. IEEE 12th Real-Time Systems Symp., Dec. 1991.
[9] M. Joseph and P. Pandya,“Finding response times in a real-time system,” The Computer J., vol. 29, no. 5, pp. 390-395, Oct. 1986.
[10] N. Audlsey,A. Burns,A. Richardson,, and A. Wellings,“Hard real-time scheduling: The deadline monotonic approach,” IEEE Workshop on Real-Time Operating Systems and Software, May 1991.
[11] L. Sha, R. Rajkuma, and J.P. Lehoczky, "Priority Inheritance Protocols: An Approach to Real-Time Synchronization," IEEE Trans. Computers, vol. 39, no. 9, pp. 1,175-1,185, Sept. 1990.
[12] J. Leung and J. Whitehead,“On the complexity of fixed-priority scheduling of periodic real-timetasks,” Performance Evaluation, vol. 2, no. 4, pp. 237-250, Dec. 1980.
[13] N.C. Audsley, A. Burns, M. Richardson, K. Tindell, and A. Wellings, "Applying New Scheduling Theory to Static Priority Preemptive Scheduling," Software Eng. J. vol. 8, no. 5, pp. 284-292, Sept. 1993.
[14] A. Burns and A. Wellings, “The Impact of an Ada Run-time System's Performance Characteristics on Scheduling Models,” Proc. 12th Ada-Europe Int'l Conf., pp. 240–248, June 1993.
[15] C.L. Liu and J.W. Layland, “Scheduling Algorithms for Multiprogramming in a Hard Real-Time Environment,” J. ACM, vol. 20, no. 1, pp. 40-61, 1973.
[16] T. Mesler,Private communication, Jan. 1992.
[17] R. Rajkumar,“Real-time synchronization protocols for shared memorymultiprocessors,” Proc. 10th IEEE Int’l Conf. Distributed Computing,Paris, May 1990.

Index Terms:
Implementation, kernel, operating system, scheduling, overheads, aerospace.
Alan Burns, Ken Tindell, Andy Wellings, "Effective Analysis for Engineering Real-Time Fixed Priority Schedulers," IEEE Transactions on Software Engineering, vol. 21, no. 5, pp. 475-480, May 1995, doi:10.1109/32.387477
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