Maintaining data temporal consistency in distributed real-time systems

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

16 Scopus Citations
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Detail(s)

Original languageEnglish
Pages (from-to)387-429
Journal / PublicationReal-Time Systems
Volume48
Issue number4
Publication statusPublished - Jul 2012

Abstract

Previous works on maintaining temporal consistency of real-time data objects mainly focuses on real-time database systems in which the transmission delays (jitters) of update jobs are simply ignored. However, this assumption does not hold in distributed real-time systems where the jitters of the update jobs can be large and change unpredictably with time. In this paper, we examine the design problems when the More-Less (ML) approach (Xiong and Ramamritham in Proc. of the IEEE realtime systems symposium 1999; IEEE Trans Comput 53: 567-583, 2004), known to be an efficient scheme for maintaining temporal consistency of real-time data objects, is applied in a distributed real-time system environment. We propose two new extensions based on ML, called Jitter-based More-Less (JB-ML) and Statistical Jitterbased More-Less (SJB-ML) to address the jitter problems. JB-ML assumes that in the system the jitter is a constant for each update task, and it provides a deterministic guarantee in temporal consistency of the real-time data objects. SJB-ML further relaxes this restriction and provides a statistical guarantee based on the given QoS requirements of the real-time data objects. We demonstrate through extensive simu- lation experiments that both JB-ML and SJB-ML are effective approaches and they significantly outperform ML in terms of improving schedulability. © 2012 Springer Science+Business Media, LLC.

Research Area(s)

  • Data freshness, Real-time databases, Scheduling and jitters, Temporal consistency

Citation Format(s)

Maintaining data temporal consistency in distributed real-time systems. / Wang, Jiantao; Han, Song; Lam, Kam-Yiu; Mok, Aloysius K.

In: Real-Time Systems, Vol. 48, No. 4, 07.2012, p. 387-429.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review