A synthetic utilization bound for aperiodic tasks with resource requirements

Utilization bounds for schedulability of aperiodic tasks are new in real-time scheduling literature. All aperiodic bounds known to date apply only to independent tasks. They either assume a liquid task model (one with infinitely many infinitesimal tasks) or are limited to deadline-monotonic and earliest-deadline first scheduling. In this paper, the authors make two important contributions. First, they derive the first aperiodic utilization bound that considers a task model with resource requirements. Second, the new bound is a function of a parameter called preemptable deadline ratio that depends on the scheduling policy. We show that many scheduling policies can be classified by this parameter allowing per-policy bounds to be derived. Simulation results demonstrating the applicability of aperiodic utilization bounds are presented.

[1]  Wei-Kuan Shih,et al.  Modified Rate-Monotonic Algorithm for Scheduling Periodic Jobs with Deferred Deadlines , 1991, IEEE Trans. Software Eng..

[2]  Giorgio C. Buttazzo,et al.  A hyperbolic bound for the rate monotonic algorithm , 2001, Proceedings 13th Euromicro Conference on Real-Time Systems.

[3]  Krithi Ramamritham,et al.  Distributed Scheduling of Tasks with Deadlines and Resource Requirements , 1989, IEEE Trans. Computers.

[4]  Daniel F. García,et al.  Minimum and maximum utilization bounds for multiprocessor rate monotonic scheduling , 2004, IEEE Transactions on Parallel and Distributed Systems.

[5]  Butler W. Lampson,et al.  Experience with processes and monitors in Mesa , 1980, CACM.

[6]  Marco Caccamo,et al.  Aperiodic servers with resource constraints , 2001, Proceedings 22nd IEEE Real-Time Systems Symposium (RTSS 2001) (Cat. No.01PR1420).

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

[8]  John P. Lehoczky,et al.  Algorithms for scheduling hard aperiodic tasks in fixed-priority systems using slack stealing , 1994, 1994 Proceedings Real-Time Systems Symposium.

[9]  Daniel F. García,et al.  Worst-case utilization bound for EDF scheduling on real-time multiprocessor systems , 2000, Proceedings 12th Euromicro Conference on Real-Time Systems. Euromicro RTS 2000.

[10]  P. Mohapatra,et al.  Lifetime behavior and its impact on Web caching , 1999, Proceedings 1999 IEEE Workshop on Internet Applications (Cat. No.PR00197).

[11]  Chenyang Lu,et al.  Schedulability analysis and utilization bounds for highly scalable real-time services , 2001, Proceedings Seventh IEEE Real-Time Technology and Applications Symposium.

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

[13]  Wa Halang,et al.  REAL-TIME SYSTEMS .1. , 1990 .

[14]  James W. Layland,et al.  Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment , 1989, JACM.

[15]  Giuseppe Lipari,et al.  Sharing resources among periodic and aperiodic tasks with dynamic deadlines , 1999, Proceedings 20th IEEE Real-Time Systems Symposium (Cat. No.99CB37054).

[16]  Theodore P. Baker,et al.  Aperiodic servers in a deadline scheduling environment , 2005, Real-Time Systems.

[17]  Arkady Kanevsky,et al.  Fixed-priority scheduling of real-time systems using utilization bounds , 1996, J. Syst. Softw..

[18]  Giuseppe Lipari,et al.  Schedulability analysis of periodic and aperiodic tasks with resource constraints , 2000, J. Syst. Archit..

[19]  Tei-Wei Kuo,et al.  Load adjustment in adaptive real-time systems , 1991, [1991] Proceedings Twelfth Real-Time Systems Symposium.

[20]  Björn Andersson,et al.  The aperiodic multiprocessor utilization bound for liquid tasks , 2002, Proceedings. Eighth IEEE Real-Time and Embedded Technology and Applications Symposium.

[21]  Dong-Ik Oh,et al.  Utilization Bounds for N-Processor Rate Monotone Scheduling with Static Processor Assignment , 1998, Real-Time Systems.