Contributo in atti di convegno, 2007, ENG, 10.1145/1277741.1277775

The impact of caching on search engines

Baeza-Yates R.; Gionis A.; Junqueira F.; Murdock V.; Plachouras V.; Silvestri F.

Yahoo! Research, Barcelona, Spain; Yahoo! Research, Barcelona, Spain; Yahoo! Research, Barcelona, Spain; Yahoo! Research, Barcelona, Spain; Yahoo! Research, Barcelona, Spain; CNR-ISTI, Pisa, Italy

In this paper we study the trade-offs in designing efficient caching systems for Web search engines. We explore the impact of different approaches, such as static vs. dynamic caching, and caching query results vs. caching posting lists. Using a query log spanning a whole year we explore the limitations of caching and we demonstrate that caching posting lists can achieve higher hit rates than caching query answers. We propose a new algorithm for static caching of posting lists, which outperforms previous methods. We also study the problem of finding the optimal way to split the static cache between answers and posting lists. Finally, we measure how the changes in the query log affect the effectiveness of static caching, given our observation that the distribution of the queries changes slowly over time. Our results and observations are applicable to different levels of the data-access hierarchy, for instance, for a memory/disk layer or a broker/remote server layer.

30th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, pp. 183–190, Amsterdam, Netherland, 23-27 July 2007

Keywords

H.3.3 Information Search and Retrieval. Search process, H.3.4 Systems and Software. Distributed systems, H.3.4 Systems and Software. Performance evaluation (efficiency and effectiveness), Caching, Web search

CNR authors

Silvestri Fabrizio

CNR institutes

ISTI – Istituto di scienza e tecnologie dell'informazione "Alessandro Faedo"

ID: 91700

Year: 2007

Type: Contributo in atti di convegno

Creation: 2009-06-16 00:00:00.000

Last update: 2018-03-05 11:02:32.000

External IDs

CNR OAI-PMH: oai:it.cnr:prodotti:91700

DOI: 10.1145/1277741.1277775

Scopus: 2-s2.0-36448931586