An Analytical Solution for Probabilistic Guarantees of Reservation Based Soft Real-Time Systems
Abstract
We show a methodology for the computation of the probability of deadline miss for a periodic real-time task scheduled by a resource reservation algorithm. We propose a modelling technique for the system that reduces the computation of such a probability to that of the steady state probability of an infinite state Discrete Time Markov Chain with a periodic structure. This structure is exploited to develop an efficient numeric solution where different accuracy/computation time trade-offs can be obtained by operating on the granularity of the model. More importantly we offer a closed form conservative bound for the probability of a deadline miss. Our experiments reveal that the bound remains reasonably close to the experimental probability in one real-time application of practical interest. When this bound is used for the optimisation of the overall Quality of Service for a set of tasks sharing the CPU, it produces a good sub-optimal solution in a small amount of time.
Cite
@article{arxiv.1604.08004,
title = {An Analytical Solution for Probabilistic Guarantees of Reservation Based Soft Real-Time Systems},
author = {Luigi Palopoli and Daniele Fontanelli and Luca Abeni and Bernardo Villalba Frías},
journal= {arXiv preprint arXiv:1604.08004},
year = {2016}
}
Comments
IEEE Transactions on Parallel and Distributed Systems, Volume:27, Issue: 3, March 2016