Performance evaluation of telecommunication networks based on multi-regime fluid queues
Author
Kankaya, Hüseyin Emre
Advisor
Aykanat, Cevdet
Date
2009Publisher
Bilkent University
Language
English
Type
ThesisItem Usage Stats
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Show full item recordAbstract
Today’s state-of-the-art search engines utilize the inverted index data structure
for fast text retrieval on large document collections. To parallelize the retrieval
process, the inverted index should be distributed among multiple index servers.
Generally the distribution of the inverted index is done in either a term-based or a
document-based fashion. The performances of both schemes depend on the total
number of disk accesses and the total volume of communication in the system.
The classical approach for both distributions is to use the Central Broker
Query Evaluation Scheme (CB) for parallel text retrieval. It is known that in this
approach the central broker is heavily loaded and becomes a bottleneck. Recently,
an alternative query evaluation technique, named Pipelined Query Evaluation
Scheme (PPL), has been proposed to alleviate this problem by performing the
merge operation on the index servers. In this study, we analyze the scalability
and relative performances of the CB and PPL under various query loads to report
the benefits and drawbacks of each method.
Keywords
parallel text retrievaldocument-based distrribution
term-based distribution
pipelined query evaluation
central broker query evaluation