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by Susanne Albers
In Proc. 29th ACM Symp. on Theory of Computing
http://ls2-www.cs.uni-dortmund.de/~albers/stoc97a.ps.gz
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Abstract:
Abstract. We study a classical problem in online scheduling. A sequence of jobs must be scheduled on m identical parallel machines. As each job arrives, its processing time is known. The goal is to minimize the makespan. Bartal, Fiat, Karloff and Vohra [3] gave a deterministic online algorithm that is 1.986-competitive. Karger, Phillips and Torng [11] generalized the algorithm and proved an upper bound of 1.945. The best lower bound currently known on the competitive ratio that can be achieved by deterministic online algorithms it equal to 1.837. In this paper we present an improved deterministic online scheduling algorithm that is 1.923-competitive, for all m 2. The algorithm is based on a new scheduling strategy, i.e., it is not a generalization of the approach by Bartal et al. Also, the algorithm has a simple structure. Furthermore, we develop a better lower bound. We prove that, for general m, no deterministic online scheduling algorithm can be better than 1.852-competitive.
Citations
|
634
|
Amortized efficiency of list update and paging rules
– Sleator, Tarjan
- 1985
|
|
239
|
Bounds for certain multiprocessing anomalies
– Graham
- 1966
|
|
122
|
Scheduling parallel machines online
– Shmoys, Wein, et al.
- 1995
|
|
103
|
Online load balancing
– Azar
- 1998
|
|
102
|
New algorithms for an ancient scheduling problem
– Bartal, Fiat, et al.
- 1995
|
|
74
|
Non-clairvoyant scheduling
– Motwani, Phillips, et al.
- 1994
|
|
64
|
A better algorithm for an ancient scheduling problem
– Karger, Phillips, et al.
- 1996
|
|
44
|
On-line routing of virtual circuits with applications to load balancing and machine scheduling
– Aspnes, Azar, et al.
- 1997
|
|
43
|
An on-line scheduling heuristic with better worst case ratio than Graham’s list scheduling
– Galambos, Woeginger
- 1993
|
|
29
|
New lower and upper bounds for on-line scheduling
– Chen, Vliet, et al.
- 1994
|
|
28
|
A better lower bound for on-line scheduling
– Bartal, Karloff, et al.
- 1994
|
|
23
|
Multiprocessor scheduling with rejection
– Bartal, Leonardi, et al.
- 1996
|
|
12
|
On the performance of on-line algorithms for particular problems
– Faigle, Kern, et al.
- 1989
|
|
9
|
Computers and Intractability: A Guide to the Theory of NP-Completeness
– Garay, Johnson
- 1979
|