GET_pdf delibra

Volume 6 (1) 2000, 25-40


Błażewicz Jacek 1, Machowiak M. 1, Mounié G. 2, Trystram D. 2

1 Institute of Computing Science, Poznań University of Technology
ul. Piotrowo 3a, 60-965 Poznań, Poland
2ID-IMAG, antenne de I’ENS IMAG
ZIRST de Montbonnot, 51 rue Jean Kuntzman
38330 Montbonnot Saint Martin, France

DOI:   10.12921/cmst.2000.06.01.25-40



In the paper, the problem of scheduling a set of n malleable tasks on m parallel computers is considered. The tasks may be executed by several processors simultaneously and the processing speed of a task is a function of the number of processors alloted. The problem is motivated by real-life applications of parallel computer systems in scientific computing of highly parallelizable tasks. Starting from the continuous version of the problem (i. e. where the tasks may require a fractional part of the resources), we propose a general approximation algorithm with a performance guarantee equal to 2. Then, some improvements are derived that lead to a very good average behavior of the scheduling algorithm.


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