An overview of some results for reordering buffers
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Lookahead is a classic concept in the theory of online scheduling. An online algorithm without lookahead has to process tasks as soon as they arrive and without any knowledge about future tasks. With lookahead, this strict assumption is relaxed. There are different variations on the exact type of information provided to the algorithm under lookahead but arguably the most common one is to assume that, at every point in time, the algorithm has knowledge of the attributes of the next k tasks to arrive. This assumption is justified by the fact that, in practice, tasks may not always strictly arrive one-by-one and therefore, a certain number of tasks are always waiting in a queue to be processed.
In recent years, so-called reordering buffers have been studied as a sensible generalization of lookahead. The basic idea is that, in problem settings where the order in which the tasks are processed is not important, we can permit a scheduling algorithm to choose to process any task waiting in the queue. This stands in contrast to lookahead, where the algorithm has knowledge of all the tasks in the queue but still has to process them in the order they arrived. We discuss some of the results for reordering buffers for different scheduling problems.
KeywordsOnline algorithms Reordering buffers Competitive analysis Survey
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- 1.Albers S (2004) New results on web caching with request reordering. In: Proceedings of the 16th ACM symposium on parallel algorithms and architectures (SPAA), pp 84–92 Google Scholar
- 3.Asahiro Y, Kawahara K, Miyano E (2010) NP-hardness of the sorting buffer problem on the uniform metric. Unpublished manuscript Google Scholar
- 5.Avigdor-Elgrabli N, Rabani Y (2010) An improved competitive algorithm for reordering buffer management. In: Proceedings of the 21st ACM-SIAM symposium on discrete algorithms (SODA), pp. 13–21 Google Scholar
- 6.Azar Y, Gamzu I, Rabani Y (October 2008) Personal communication Google Scholar
- 9.Chan H-L, Megow N, van Stee R, Sitters R (2010) The sorting buffer problem is NP-hard. CoRR, arXiv:1009.4355
- 11.Dósa G, Epstein L (2008) Online scheduling with a buffer on related machines. Journal of Combinatorial Optimization. doi:10.1007/s10878-008-9200-y
- 12.Dósa G, Epstein L (2009) Preemptive online scheduling with reordering. In: Proceedings of the 17th European symposium on algorithms (ESA), pp 456–467 Google Scholar
- 14.Englert M, Räcke H, Westermann M (2007) Reordering buffers for general metric spaces. In: Proceedings of the 39th ACM symposium on theory of computing (STOC), pp 556–564 Google Scholar
- 20.Gamzu I, Segev D (2007) Improved online algorithms for the sorting buffer problem. In: Proceedings of the 24th symposium on theoretical aspects of computer science (STACS), pp 658–669 Google Scholar
- 22.Khandekar R, Pandit V (2006) Online sorting buffers on line. In: Proceedings of the 23rd symposium on theoretical aspects of computer science (STACS), pp 584–595 Google Scholar
- 23.Li S, Zhou Y, Sun G, Chen F (2007) Study on parallel machine scheduling problem with buffer. In: Proceedings of the 2nd international multi-symposiums on computer and computational sciences, pp 278–273 Google Scholar
- 25.Räcke H, Sohler C, Westermann M (2002) Online scheduling for sorting buffers. In: Proceedings of the 10th European symposium on algorithms (ESA), pp 820–832 Google Scholar
- 26.Rudin JF III (2001) Improved bound for the online scheduling problem. PhD thesis, University of Texas at Dallas Google Scholar