Cited by 8,433Real-Time Systems SchedulingParallel Computing and Optimization TechniquesEmbedded Systems Design Techniques

Scheduling algorithms for multiprogramming in a hard-real-time environment

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Liu, C. L., Layland, James W.·1973·Journal of the ACM

Abstract

The problem of multiprogram scheduling on a single processor is studied from the viewpoint of the characteristics peculiar to the program functions that need guaranteed service. It is shown that an optimum fixed priority scheduler possesses an upper bound to processor utilization which may be as low as 70 percent for large task sets. It is also shown that full processor utilization can be achieved by dynamically assigning priorities on the basis of their current deadlines. A combination of these two scheduling techniques is also discussed.

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Crossref · 10.1145/321738.321743

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  • Response times can be almost certainly guaranteed up to a load factor of about 80% under rate monotonic scheduling.

    “In a typical scheduling method called rate monotonic scheduling (RMS) [29], it has been shown that response times can be almost certainly guaranteed up to a load factor of about 80%.”

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Research works printed but not linked: 1

  1. RECEIVED MARCH 1970; REVISED JANUARY 1972 Journal of the Associatlon ior Cornputmg Machinery, Vol. 20, No. I, January 1973

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Authors
Liu, C. L., & Layland, J. W.
Affiliations
  • University of Illinois Urbana-Champaign (US)
  • California Institute of Technology (US)
Venue
Journal of the ACM
Published
1973-01
Volume
20
Issue
1
Pages
46-61
ISSN
  • 0004-5411 (ISSN-L)
  • 1557-735X
OpenAlex
W2109488193
Cited by
8,433
References
12
Citations by year
2026: 137 · 2025: 103 · 2024: 112 · 2023: 138 · 2022: 139 · 2021: 153 · 2020: 188 · 2019: 222 · 2018: 232 · 2017: 242 · 2016: 269 · 2015: 308 · 2014: 347 · 2013: 314 · 2012: 321
FWCI
4.75
Type
journal article
Language
en
Open access
Locations
Journal of the ACM (publishedVersion)
Funders
National Aeronautics and Space Administration
Topics
  • Physical Sciences › Computer Science › Hardware and Architecture › Real-Time Systems Scheduling
  • Physical Sciences › Computer Science › Hardware and Architecture › Parallel Computing and Optimization Techniques
  • Physical Sciences › Computer Science › Hardware and Architecture › Embedded Systems Design Techniques
Keywords
multiprogramming, hard real-time systems, scheduling algorithms, fixed-priority scheduling, CPU utilization, guaranteed service, single machine scheduling, task sets

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