<abstract xmlns="http://www.w3.org/1999/xhtml"><p>When there is a mismatch between the cardinality of a periodic task set and the priority levels supported by the underlying hardware systems, multiple tasks are grouped into one class so as to maintain a specific level of confidence in their accuracy. However, such a transformation is achieved at the expense of the loss of schedulability of the original task set. We further investigate the aforementioned problem and report the following contributions: (i) a novel technique for mapping unlimited priority tasks into a reduced number of classes that do not violate the schedulability of the original task set and (ii) an efficient feasibility test that eliminates insufficient points during the feasibility analysis. The theoretical correctness of both contributions is checked through formal verifications. Moreover, the experimental results reveal the superiority of our work over the existing feasibility tests by reducing the number of scheduling points that are needed otherwise.</p></abstract>

When there is a mismatch between the cardinality of a periodic task set and the priority levels supported by the underlying hardware systems, multiple tasks are grouped into one class so as to maintain a specific level of confidence in their accuracy. However, such a transformation is achieved at the expense of the loss of schedulability of the original task set. We further investigate the aforementioned problem and report the following contributions: (i) a novel technique for mapping unlimited priority tasks into a reduced number of classes that do not violate the schedulability of the original task set and (ii) an efficient feasibility test that eliminates insufficient points during the feasibility analysis. The theoretical correctness of both contributions is checked through formal verifications. Moreover, the experimental results reveal the superiority of our work over the existing feasibility tests by reducing the number of scheduling points that are needed otherwise.

Maintaining the Feasibility of Hard Real–Time Systems with a Reduced Number of Priority Levels

Department of Computer Sciences, COMSATS Institute of Information Technology, Islamabad 46000, Pakistan

College of Computer Science and Information Technology, University of Dammam, Saudi Arabia

Institute of Computer Science, Cracow University of Technology, ul. Warszawska 24, 31-155 Cracow, Poland

Institute of Control and Computation Engineering, Warsaw University of Technology, Wąwozowa 18, 02-796 Warsaw, Poland

International Journal of Applied Mathematics and Computer Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

When there is a mismatch between the cardinality of a periodic task set and the priority levels supported by the underlying hardware systems, multiple tasks...

Maintaining the Feasibility of Hard Real–Time Systems with a Reduced Number of Priority Levels

Publicado en línea: 30 dic 2015

Páginas: 709 - 722

Recibido: 11 oct 2014

DOI: https://doi.org/10.1515/amcs-2015-0051

Palabras clave
real-time systems, feasibility analysis, fixed-priority scheduling, rate monotonic algorithm, online scheduling

© 2015 Muhammad Bilal Qureshi et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Maintaining the Feasibility of Hard Real–Time Systems with a Reduced Number of Priority Levels

Publicado en línea: 30 dic 2015

Páginas: 709 - 722

Recibido: 11 oct 2014

DOI: https://doi.org/10.1515/amcs-2015-0051

Palabras clavereal-time systems, feasibility analysis, fixed-priority scheduling, rate monotonic algorithm, online scheduling

© 2015 Muhammad Bilal Qureshi et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Palabras clave
real-time systems, feasibility analysis, fixed-priority scheduling, rate monotonic algorithm, online scheduling