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Allocating hard real-time tasks: An NP-Hard problem made easy

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Abstract

A distributed hard real time system can be composed from a number of communicating tasks. One of the difficulties with building such systems is the problem of where to place the tasks. In general there are P T ways of allocating T tasks to P processors, and the problem of finding an optimal feasible allocation (where all tasks meet physical and timing constraints) is known to be NP-Hard. This paper describes an approach to solving the task allocation problem using a technique known as simulated annealing. It also defines a distributed hard real-time architecture and presents new analysis which enables timing requirements to be guaranteed.

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Authors and Affiliations

  1. Real Time Systems Research Group, Department of Computer Science, University of York, England

    K. W. Tindell & A. Burns

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  1. K. W. Tindell
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  2. A. Burns
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  3. A. J. Wellings
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Additional information

This work was supported in part by British Aerospace (Commercial Aircraft) Ltd, and the UK Department of Trade and Industry.

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Tindell, K.W., Burns, A. & Wellings, A.J. Allocating hard real-time tasks: An NP-Hard problem made easy. The Journal of Real-Time Systems 4, 145–165 (1992). https://doi.org/10.1007/BF00365407

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  • DOI: https://doi.org/10.1007/BF00365407

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