A Modified Least-Laxity-First scheduling algorithm for real-time tasks

Author

Oh, Sung-Heun ; Yang, Seung-Min

Author_Institution

Sch. of Comput., Soongsil Univ., Seoul, South Korea

fYear

1998

fDate

27-29 Oct 1998

Firstpage

31

Lastpage

36

Abstract

The Least-Laxity-First (LLF) scheduling algorithm assigns higher priority to a task with the least laxity, and has been proved to be optimal for uniprocessor systems. The algorithm, however is impractical to implement because laxity tie results in the frequent context switches among the tasks. The Modified Least-Laxity-First (MLLF) scheduling algorithm proposed in this paper solves the problem of the LLF scheduling algorithm by reducing the number of context switches significantly. By reducing the system overhead due to unnecessary context switches, the MLLF scheduling algorithm avoids the degradation of system performance and conserves more system resources for unanticipated aperiodic tasks. We propose the MLLF scheduling algorithm and prove its optimality. We show the performance enhancement of the proposed MLLF scheduling algorithm by using simulation results

Keywords

real-time systems; resource allocation; scheduling; software performance evaluation; Modified Least-Laxity-First; context switches; performance enhancement; real-time tasks; scheduling algorithm; simulation; system overhead; system performance; task priority; uniprocessor systems; Contracts; Degradation; Processor scheduling; Real time systems; Scheduling algorithm; Switches; System performance;

fLanguage

English

Publisher

ieee

Conference_Titel

Real-Time Computing Systems and Applications, 1998. Proceedings. Fifth International Conference on

Conference_Location

Hiroshima

Print_ISBN

0-8186-9209-X

Type

conf

DOI

10.1109/RTCSA.1998.726348

Filename

726348