Exploitation of different types of locality for Web caches

G. Karakostas, D. N. Serpanos

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

18 Citations (Scopus)

Abstract

Object access distribution in the Web is governed by Zipf's law, in general. This property leads to effective Web caches, which store the most popular objects and typically employ the LFU replacement policy, which achieves high, and often the highest, cache hit rates. However, Web cache design based only on Zipf's law has two main disadvantages: (i) it does not exploit the temporal and spatial locality of user accesses on a per session basis, and (ii) LFU implementation is costly and impractical in many environments, because it requires statistics on all objects accessed since the beginning of a cache's operation. We consider all parameters of locality of references in the Web (temporal, spatial and popularity) and draw an analogy with processor caches. Given cache replacement policies that address different locality characteristics, we argue that there exist replacement algorithms that combine these characteristics and achieve high performance at a low cost. We describe the Window-LFU (W-LFU), a policy that combines LFU and LRU and achieves better performance than LFU at lower cost. W-LFU exploits both Zipf's law, and temporal locality by using the accesses in a recent time-window. Simulations with actual traces indicate that W-LFU provides better results than theoretically expected.

Original languageEnglish
Title of host publicationProceedings - IEEE Symposium on Computers and Communications
Pages207-212
Number of pages6
DOIs
Publication statusPublished - 1 Dec 2002
Externally publishedYes
Event7th International Symposium on Computers and Communications, ISCC 2002 - Taormina-Giardini Naxos, Italy
Duration: 1 Jul 20024 Jul 2002

Other

Other7th International Symposium on Computers and Communications, ISCC 2002
CountryItaly
CityTaormina-Giardini Naxos
Period1/7/024/7/02

Fingerprint

Locality
Cache
Exploitation
Zipf's law
Costs
Replacement Policy
Statistics
Time Windows
Hits
Replacement
Analogy
High Performance
Trace
Object
Simulation

ASJC Scopus subject areas

  • Computer Networks and Communications
  • Computer Science Applications
  • Software
  • Mathematics(all)
  • Signal Processing

Cite this

Karakostas, G., & Serpanos, D. N. (2002). Exploitation of different types of locality for Web caches. In Proceedings - IEEE Symposium on Computers and Communications (pp. 207-212). [1021680] https://doi.org/10.1109/ISCC.2002.1021680

Exploitation of different types of locality for Web caches. / Karakostas, G.; Serpanos, D. N.

Proceedings - IEEE Symposium on Computers and Communications. 2002. p. 207-212 1021680.

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

Karakostas, G & Serpanos, DN 2002, Exploitation of different types of locality for Web caches. in Proceedings - IEEE Symposium on Computers and Communications., 1021680, pp. 207-212, 7th International Symposium on Computers and Communications, ISCC 2002, Taormina-Giardini Naxos, Italy, 1/7/02. https://doi.org/10.1109/ISCC.2002.1021680
Karakostas G, Serpanos DN. Exploitation of different types of locality for Web caches. In Proceedings - IEEE Symposium on Computers and Communications. 2002. p. 207-212. 1021680 https://doi.org/10.1109/ISCC.2002.1021680
Karakostas, G. ; Serpanos, D. N. / Exploitation of different types of locality for Web caches. Proceedings - IEEE Symposium on Computers and Communications. 2002. pp. 207-212
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