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Soft Real-Time Scheduling

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Handbook of Real-Time Computing

Abstract

The notion of temporal correctness applicable to a hard real-time system is quite categorical: such a system is deemed to be temporally correct if and only if no task ever misses a deadline. In contrast, soft real-time systems are sometimes permitted to miss deadlines, and there are a variety of ways in which the term “sometimes” might plausibly be defined. As a result, several different notions of soft real-time correctness have been studied in the literature. In this chapter, a survey of research results pertaining to several such notions is presented. Additionally, the related issue of overload management is considered. Overloads may be common in soft real-time systems because such systems are typically provisioned less pessimistically than hard real-time ones.

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Authors and Affiliations

  1. Department of Computer Science, The University of North Carolina, Chapel Hill, NC, USA

    Jeremy P. Erickson & James H. Anderson

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  1. Jeremy P. Erickson
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  2. James H. Anderson
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Correspondence to James H. Anderson .

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Editors and Affiliations

  1. School of Computer Science, Queensland University of Technology, Brisbane, QLD, Australia

    Yu-Chu Tian

  2. School of Electrical and Information Engineering, The University of Sydney, Sydney, NSW, Australia

    David Charles Levy

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Erickson, J.P., Anderson, J.H. (2022). Soft Real-Time Scheduling. In: Tian, YC., Levy, D.C. (eds) Handbook of Real-Time Computing. Springer, Singapore. https://doi.org/10.1007/978-981-287-251-7_4

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