The EDL Server for Scheduling Periodic and Soft Aperiodic Tasks with Resource Constraints

In this paper, we are concerned with the problem of serving soft aperiodic tasks on a uniprocessor system where periodic tasks are scheduled on a dynamic-priority, preemptive basis and exclusively access to critical sections. Scheduling of tasks is handled by the Dynamic Priority Ceiling Protocol working with an Earliest Deadline scheduler. Our analysis determines the maximum processing time which may be stolen from periodic tasks without jeopardizing both their timing constraints and resource consistency. It provides the basis for an on-line scheduling algorithm, the EDL Server, to deal with the minimization of response times for soft aperiodic tasks.

[1]  J. Leung,et al.  A Note on Preemptive Scheduling of Periodic, Real-Time Tasks , 1980, Inf. Process. Lett..

[2]  Jay K. Strosnider,et al.  The Deferrable Server Algorithm for Enhanced Aperiodic Responsiveness in Hard Real-Time Environments , 1987, IEEE Trans. Computers.

[3]  Lui Sha,et al.  Priority Inheritance Protocols: An Approach to Real-Time Synchronization , 1990, IEEE Trans. Computers.

[4]  Marco Spuri,et al.  How to Integrate Precedence Constraints and Shared Resources in Real-Time Scheduling , 1994, IEEE Trans. Computers.

[5]  John P. Lehoczky,et al.  On-line scheduling of hard deadline aperiodic tasks in fixed-priority systems , 1993, 1993 Proceedings Real-Time Systems Symposium.

[6]  Maryline Chetto,et al.  Some Results of the Earliest Deadline Scheduling Algorithm , 1989, IEEE Transactions on Software Engineering.

[7]  Lui Sha,et al.  Exploiting unused periodic time for aperiodic service using the extended priority exchange algorithm , 1988, Proceedings. Real-Time Systems Symposium.

[8]  Joseph Y.-T. Leung,et al.  On the complexity of fixed-priority scheduling of periodic, real-time tasks , 1982, Perform. Evaluation.

[9]  M. Silly.  A dynamic scheduling algorithm for semi-hard real-time environments , 1994, Proceedings Sixth Euromicro Workshop on Real-Time Systems.

[10]  John P. Lehoczky,et al.  An optimal algorithm for scheduling soft-aperiodic tasks in fixed-priority preemptive systems , 1992, [1992] Proceedings Real-Time Systems Symposium.

[11]  Chung Laung Liu,et al.  Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment , 1989, JACM.

[12]  Ismael Ripoll,et al.  An Optimal Algorithm for Scheduling Soft Aperiodic Tasks in Dynamic-Priority Preemptive Systems , 1997, IEEE Trans. Software Eng..

[13]  Min-Ih Chen.  Schedulability analysis of resource access control protocols in real-time systems , 1992 .

[14]  Marco Spuri,et al.  Efficient aperiodic service under earliest deadline scheduling , 1994, 1994 Proceedings Real-Time Systems Symposium.

[15]  Jay K. Strosnider,et al.  ENHANCED APERIODIC RESPONSIVENESS IN HARD REAL-TIME ENVIRONMENTS. , 1987, RTSS 1987.