Abstract
We consider the problem to minimize the weighted sum of completion times in nonpreemptive parallel machine scheduling. In a landmark paper from 1986, Kawaguchi and Kyan showed that scheduling the jobs according to the WSPT rule -also known as Smith's rule- has a performance guarantee of 1.207. They also gave an instance to show that this bound is tight. We consider the stochastic variant of this problem in which the processing times are exponentially distributed random variables. We show, somehow counterintuitively, that the performance guarantee of the WSEPT rule, the stochastic analogue of WSPT, is not better than 1.243. This constitutes the first lower bound for WSEPT in this setting, and in particular, it sheds new light on the fundamental differences between deterministic and stochastic scheduling problems.
Original language | Undefined |
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Title of host publication | 8th International Workshop on Approximation and Online Algorithms, WAOA 2010 |
Editors | K. Jansen, R Solis-Oba |
Place of Publication | Heidelberg |
Publisher | Springer |
Pages | 142-153 |
Number of pages | 12 |
ISBN (Print) | 978-3-642-18317-1 |
DOIs | |
Publication status | Published - 2011 |
Event | 8th International Workshop on Approximation and Online Algorithms 2010 - University of Liverpool, Liverpool, United Kingdom Duration: 9 Sep 2010 → 10 Sep 2010 Conference number: 8 |
Publication series
Name | Lecture Notes in Computer Science |
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Publisher | Springer Verlag |
Volume | 6534 |
ISSN (Print) | 0302-9743 |
ISSN (Electronic) | 1611-3349 |
Conference
Conference | 8th International Workshop on Approximation and Online Algorithms 2010 |
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Abbreviated title | WAOA 2010 |
Country | United Kingdom |
City | Liverpool |
Period | 9/09/10 → 10/09/10 |
Keywords
- METIS-277547
- IR-76015
- Scheduling
- EWI-19621
- Stochastic Scheduling
- WSPT
- Exponential distribution