Testing of synchronization conditions for distributed real-time applications

  • Ajay D. Kshemkalyani
Workshop on Parallel and Distributed Real-Time Systems David Andrews, UofA, USA P.D.V. van der Stok, Eindhoven University, The Netherlands Kenji Toda, Electro-tech Laboratory, Japan
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1388)


A set of synchronization relations between distributed nonatomic events was recently proposed to provide real-time applications with a fine level of discrimination in the specification of causality relations and synchronization conditions. For a pair of distributed nonatomic events X and Y, the evaluation of the synchronization relations requires | NX| x | NY | integer comparisons, where | Nx | and | Ny |, respectively, are the number of nodes on which the two nonatomic events X and Y occur. In this paper, we show that this polynomial complexity of evaluation can by simplified using properties of partial orders to a linear complexity. Specifically, we show that most relations can be evaluated in min(|NX |, |NY|) integer comparisons, some in |NX| integer comparisons, and the others in |NY| integer comparisons. These linear time evaluation conditions enable the real-time applications to detect the relations efficiently.


Time Synchronization Distributed system Efficient measures 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Ajay D. Kshemkalyani
    • 1
  1. 1.Dept. of Electrical and Computer Engineering and Computer ScienceUniversity of CincinnatiCincinnatiUSA

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