Abstract
We use the duality of linear programing to obtain exact formulas of competitive ratio for the semi-online preemptive scheduling on three and four machines. We use the linear programs from [3]. Namely we consider the online scheduling and the semi-online scheduling with known sum of processing times. We solve the linear programs symbolically by examining all basic solution candidates. All solutions are obtained by a computer but all are verifiable by hand.
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Ebenlendr, T. (2010). Semi-online Preemptive Scheduling: Study of Special Cases. In: Wyrzykowski, R., Dongarra, J., Karczewski, K., Wasniewski, J. (eds) Parallel Processing and Applied Mathematics. PPAM 2009. Lecture Notes in Computer Science, vol 6068. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-14403-5_2
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DOI: https://doi.org/10.1007/978-3-642-14403-5_2
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-14402-8
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