Second Chance: A Hybrid Approach for Dynamic Result Caching in Search Engines

Altıngövde, İsmail Sengör
Barla Cambazoglu, B.
Ulusoy, Ozgur
Result caches are vital for efficiency of search engines. In this work, we propose a novel caching strategy in which a dynamic result cache is split into two layers: an HTML cache and a docID cache. The HTML cache in the first layer stores the result pages computed for queries. The docID cache in the second layer stores ids of documents in search results. Experiments under various scenarios show that, in terms of average query processing time, this hybrid caching approach outperforms the traditional approach, which relies only on the HTML cache.
33rd European Conference on Information Retrieval


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The result cache is a vital component for efficiency of large-scale web search engines, and maintaining the freshness of cached query results is the current research challenge. As a remedy to this problem, our work proposes a new mechanism to identify queries whose cached results are stale. The basic idea behind our mechanism is to maintain and compare generation time of query results with update times of posting lists and documents to decide on staleness of query results. The proposed technique is evaluate...
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We propose a new mechanism to predict stale queries in the result cache of a search engine. The novelty of our approach is in the use of timestamps in staleness predictions. We show that our approach incurs very little overhead on the system while its prediction accuracy is comparable to earlier works.
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Citation Formats
İ. S. Altıngövde, B. Barla Cambazoglu, and O. Ulusoy, “Second Chance: A Hybrid Approach for Dynamic Result Caching in Search Engines,” Dublin, IRELAND, 2011, vol. 6611, Accessed: 00, 2020. [Online]. Available: