Timestamp-based cache invalidation for search engines

Alici, Sadiye
Altıngövde, İsmail Sengör
Ozcan, Rifat
Cambazoglu, B. Barla
Ulusoy, Özgür
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.


Timestamp-based result cache invalidation for web search engines
Alici, Sadiye; Altıngövde, İsmail Sengör; Ozcan, Rifat; Cambazoglu, B. Barla; Ulusoy, Özgür (2011-01-01)
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...
Second Chance: A Hybrid Approach for Dynamic Result Caching in Search Engines
Altıngövde, İsmail Sengör; Barla Cambazoglu, B.; Ulusoy, Ozgur (2011-01-01)
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 approac...
Advanced methods for result and score caching in web search engines
Yafay, Erman.; Altıngövde, İsmail Sengör; Department of Computer Engineering (2019)
Search engines employ caching techniques in main memory to improve system efficiency and scalability. In this thesis, we focus on improving the cache performance for web search engines where our contributions can be separated into two main parts. Firstly, we investigate the impact of the sample size for frequency statistics for most popular cache eviction strategies in the literature, and show that cache performance improves with larger samples, i.e., by storing the frequencies of all (or, most of) the quer...
Cost-aware result caching strategies for meta-search engines
Bakkal, Emre; Altıngövde, İsmail Sengör; Department of Computer Engineering (2015)
Meta-search engines are tools that generate top-k search results of a query by combining local top-k search results retrieved from various data sources in parallel. A result cache that stores the results of the previously seen queries is a crucial component in a meta-search engine to improve the efficiency, scalability and availability of the system. Our goal in this thesis is to design and analyze different cost-aware and dynamic result caching strategies to be used in meta-search engines. To this end, as ...
Limitations and improvement opportunities for implicit result diversification in search engines
Ulu, Yaşar Barış; Altıngövde, İsmail Sengör; Department of Computer Engineering (2019)
Search engine users essentially expect to find the relevant results for their query. Additionally, the results of the query should contain different possible query intents, which leads to the well-known problem of search result diversification. Our work first investigates the limitations of implicit search result diversification, and in particular, reveals that typical optimization tricks (such as clustering) may not necessarily improve the diversification effectiveness. Then, as our second contribution, we...
Citation Formats
S. Alici, İ. S. Altıngövde, R. Ozcan, B. B. Cambazoglu, and Ö. Ulusoy, “Timestamp-based cache invalidation for search engines,” 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38934.