The Fully Polynomial-Time Approximation Scheme for Feasibility Analysis in Static-Priority Systems with Arbitrary Relative Deadlines Revisited

Thi Huyen Chau Nguyen (1) , Pascal Richard (1) , Nathan Fisher (2)

1 LISI [Poitiers] - Laboratoire d'informatique scientifique et industrielle [EA 1232]
2 Department of computer science [Detroit]

We consider sporadic tasks with static priorities and arbitrary deadlines to be executed upon a uniprocessor platform. Pseudo-polynomial time algorithms are known for computing worst-case response times for this task model. Fisher and Baruah proposed in 2005 an approximate feasibility test running in polynomial time according to an accuracy parameter $\epsilon$ (i.e., approximation scheme or \FPTAS). We show that this algorithm is valid for the Rate Monotonic scheduling policy, but must be slightly modified to be applicable for arbitrary priority assignment. We also introduce some improvements to achieve a higher efficiency. We illustrate the improved algorithm on a detailed example.

Domaines: Systèmes embarqués

Thi Huyen Chau Nguyen, Pascal Richard, Nathan Fisher. The Fully Polynomial-Time Approximation Scheme for Feasibility Analysis in Static-Priority Systems with Arbitrary Relative Deadlines Revisited. 18th International Conference on Real-Time and Network Systems, Nov 2010, Toulouse, France. pp.21-30. ⟨hal-00544444⟩