Computers and Intractability: A Guide to the Theory of NP-Completeness
Computers and Intractability: A Guide to the Theory of NP-Completeness
Online Scheduling for Sorting Buffers
ESA '02 Proceedings of the 10th Annual European Symposium on Algorithms
Reordering buffers for general metric spaces
Proceedings of the thirty-ninth annual ACM symposium on Theory of computing
Exploiting locality: approximating sorting buffers
Journal of Discrete Algorithms
Online and offline algorithms for the sorting buffers problem on the line metric
Journal of Discrete Algorithms
A study of replacement algorithms for a virtual-storage computer
IBM Systems Journal
An improved competitive algorithm for reordering buffer management
SODA '10 Proceedings of the twenty-first annual ACM-SIAM symposium on Discrete Algorithms
Almost tight bounds for reordering buffer management
Proceedings of the forty-third annual ACM symposium on Theory of computing
Reordering buffer management for non-uniform cost models
ICALP'05 Proceedings of the 32nd international conference on Automata, Languages and Programming
A bicriteria approximation for the reordering buffer problem
ESA'12 Proceedings of the 20th Annual European conference on Algorithms
| Hi-index | 5.23 |
We consider the offline sorting buffer problem. The input is a sequence of items of different types. All items must be processed one by one by a server. The server is equipped with a random-access buffer of limited capacity which can be used to rearrange items. The problem is to design a scheduling strategy that decides upon the order in which items from the buffer are sent to the server. Each type change incurs unit cost, and thus, the objective is to minimize the total number of type changes for serving the entire sequence. This problem is motivated by various applications in manufacturing processes and computer science, and it has attracted significant attention in the last few years. The main focus has been on online competitive algorithms. Surprisingly little is known on the basic offline problem. In this paper, we show that the sorting buffer problem with uniform cost is NP-hard and, thus, close one of the most fundamental questions for the offline problem. On the positive side, we give an O(1)-approximation algorithm when the scheduler is given a buffer only slightly larger than double the original size. We also sketch a fast dynamic programming algorithm for the special case of buffer size 2.