Online algorithms for finger searching

Richard Cole, Arvind Raghunathan

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The technique of speeding up access into search structures by maintaining fingers that point to various locations of the search structure is considered. The problem of choosing, in a large search structure, locations at which to maintain fingers is treated. In particular, a server problem in which k servers move along a line segment of length m, where m is the number of keys in the search structure, is addressed. Since fingers may be arbitrarily copied, a server is allowed to jump, or fork, to a location currently occupied by another server. Online algorithms are presented and their competitiveness analyzed. It is shown that the case in which k = 2 behaves differently from the case in which k ≥ 3, by showing that there is a four-competitive algorithm for k = 2 that never forks its fingers. For k ≥ 3, it is shown that any online algorithm that does not fork its fingers can be at most Ω(m1/2)-competitive. The main result is that for k = 3 there is an online algorithm that forks and is constant competitive (independent of m, the size of the search structure). The algorithm is simple and implementable.

Original languageEnglish (US)
Title of host publicationAnnual Symposium on Foundations of Computer Science - Proceedings
PublisherPubl by IEEE
Pages480-489
Number of pages10
Volume2
StatePublished - 1990
EventProceedings of the 31st Annual Symposium on Foundations of Computer Science - St. Louis, MO, USA
Duration: Oct 22 1990Oct 24 1990

Other

OtherProceedings of the 31st Annual Symposium on Foundations of Computer Science
CitySt. Louis, MO, USA
Period10/22/9010/24/90

Fingerprint

Servers

ASJC Scopus subject areas

  • Hardware and Architecture

Cite this

Cole, R., & Raghunathan, A. (1990). Online algorithms for finger searching. In Annual Symposium on Foundations of Computer Science - Proceedings (Vol. 2, pp. 480-489). Publ by IEEE.

Online algorithms for finger searching. / Cole, Richard; Raghunathan, Arvind.

Annual Symposium on Foundations of Computer Science - Proceedings. Vol. 2 Publ by IEEE, 1990. p. 480-489.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Cole, R & Raghunathan, A 1990, Online algorithms for finger searching. in Annual Symposium on Foundations of Computer Science - Proceedings. vol. 2, Publ by IEEE, pp. 480-489, Proceedings of the 31st Annual Symposium on Foundations of Computer Science, St. Louis, MO, USA, 10/22/90.
Cole R, Raghunathan A. Online algorithms for finger searching. In Annual Symposium on Foundations of Computer Science - Proceedings. Vol. 2. Publ by IEEE. 1990. p. 480-489
Cole, Richard ; Raghunathan, Arvind. / Online algorithms for finger searching. Annual Symposium on Foundations of Computer Science - Proceedings. Vol. 2 Publ by IEEE, 1990. pp. 480-489
@inproceedings{cc6f3404f3344c54bd72ecd18fc90179,
title = "Online algorithms for finger searching",
abstract = "The technique of speeding up access into search structures by maintaining fingers that point to various locations of the search structure is considered. The problem of choosing, in a large search structure, locations at which to maintain fingers is treated. In particular, a server problem in which k servers move along a line segment of length m, where m is the number of keys in the search structure, is addressed. Since fingers may be arbitrarily copied, a server is allowed to jump, or fork, to a location currently occupied by another server. Online algorithms are presented and their competitiveness analyzed. It is shown that the case in which k = 2 behaves differently from the case in which k ≥ 3, by showing that there is a four-competitive algorithm for k = 2 that never forks its fingers. For k ≥ 3, it is shown that any online algorithm that does not fork its fingers can be at most Ω(m1/2)-competitive. The main result is that for k = 3 there is an online algorithm that forks and is constant competitive (independent of m, the size of the search structure). The algorithm is simple and implementable.",
author = "Richard Cole and Arvind Raghunathan",
year = "1990",
language = "English (US)",
volume = "2",
pages = "480--489",
booktitle = "Annual Symposium on Foundations of Computer Science - Proceedings",
publisher = "Publ by IEEE",

}

TY - GEN

T1 - Online algorithms for finger searching

AU - Cole, Richard

AU - Raghunathan, Arvind

PY - 1990

Y1 - 1990

N2 - The technique of speeding up access into search structures by maintaining fingers that point to various locations of the search structure is considered. The problem of choosing, in a large search structure, locations at which to maintain fingers is treated. In particular, a server problem in which k servers move along a line segment of length m, where m is the number of keys in the search structure, is addressed. Since fingers may be arbitrarily copied, a server is allowed to jump, or fork, to a location currently occupied by another server. Online algorithms are presented and their competitiveness analyzed. It is shown that the case in which k = 2 behaves differently from the case in which k ≥ 3, by showing that there is a four-competitive algorithm for k = 2 that never forks its fingers. For k ≥ 3, it is shown that any online algorithm that does not fork its fingers can be at most Ω(m1/2)-competitive. The main result is that for k = 3 there is an online algorithm that forks and is constant competitive (independent of m, the size of the search structure). The algorithm is simple and implementable.

AB - The technique of speeding up access into search structures by maintaining fingers that point to various locations of the search structure is considered. The problem of choosing, in a large search structure, locations at which to maintain fingers is treated. In particular, a server problem in which k servers move along a line segment of length m, where m is the number of keys in the search structure, is addressed. Since fingers may be arbitrarily copied, a server is allowed to jump, or fork, to a location currently occupied by another server. Online algorithms are presented and their competitiveness analyzed. It is shown that the case in which k = 2 behaves differently from the case in which k ≥ 3, by showing that there is a four-competitive algorithm for k = 2 that never forks its fingers. For k ≥ 3, it is shown that any online algorithm that does not fork its fingers can be at most Ω(m1/2)-competitive. The main result is that for k = 3 there is an online algorithm that forks and is constant competitive (independent of m, the size of the search structure). The algorithm is simple and implementable.

UR - http://www.scopus.com/inward/record.url?scp=0025530516&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025530516&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:0025530516

VL - 2

SP - 480

EP - 489

BT - Annual Symposium on Foundations of Computer Science - Proceedings

PB - Publ by IEEE

ER -