# Maintaining the feasibility of hard real-time systems with a reduced number of priority levels

Muhammad Bilal Qureshi; Saleh Alrashed; Nasro Min-Allah; Joanna Kołodziej; Piotr Arabas

International Journal of Applied Mathematics and Computer Science (2015)

- Volume: 25, Issue: 4, page 709-722
- ISSN: 1641-876X

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topMuhammad Bilal Qureshi, et al. "Maintaining the feasibility of hard real-time systems with a reduced number of priority levels." International Journal of Applied Mathematics and Computer Science 25.4 (2015): 709-722. <http://eudml.org/doc/275982>.

@article{MuhammadBilalQureshi2015,

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.},

author = {Muhammad Bilal Qureshi, Saleh Alrashed, Nasro Min-Allah, Joanna Kołodziej, Piotr Arabas},

journal = {International Journal of Applied Mathematics and Computer Science},

keywords = {real-time systems; feasibility analysis; fixed-priority scheduling; rate monotonic algorithm; online scheduling},

language = {eng},

number = {4},

pages = {709-722},

title = {Maintaining the feasibility of hard real-time systems with a reduced number of priority levels},

url = {http://eudml.org/doc/275982},

volume = {25},

year = {2015},

}

TY - JOUR

AU - Muhammad Bilal Qureshi

AU - Saleh Alrashed

AU - Nasro Min-Allah

AU - Joanna Kołodziej

AU - Piotr Arabas

TI - Maintaining the feasibility of hard real-time systems with a reduced number of priority levels

JO - International Journal of Applied Mathematics and Computer Science

PY - 2015

VL - 25

IS - 4

SP - 709

EP - 722

AB - 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.

LA - eng

KW - real-time systems; feasibility analysis; fixed-priority scheduling; rate monotonic algorithm; online scheduling

UR - http://eudml.org/doc/275982

ER -

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