Abstract
We give a detailed competitive analysis of a popular on-line disk scheduling algorithm, namely, LOOK. Our analysis yields a tight competitive ratio for the LOOK algorithm. By comparing and contrasting the competitive ratio of LOOK with the lower bounds of FCFS and SSTF (which are equally popular in disk scheduling), our results provide strong evidence to suggest that when the workload of disk access is heavy, LOOK outperforms SSTF and FCFS. As a by-product, our analysis also reveals (quantitatively) the role played by the degree of look-ahead in disk scheduling.
This work was supported in part by the National Science Council of the Republic of China under Grant NSC-84-2213-E-002-002.
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© 1996 Springer-Verlag Berlin Heidelberg
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Yeh, TH., Kuo, CM., Lei, CL., Yen, HC. (1996). Competitive analysis of on-line disk scheduling. In: Asano, T., Igarashi, Y., Nagamochi, H., Miyano, S., Suri, S. (eds) Algorithms and Computation. ISAAC 1996. Lecture Notes in Computer Science, vol 1178. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0009512
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DOI: https://doi.org/10.1007/BFb0009512
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