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dc.identifier.urihttp://hdl.handle.net/11401/77297
dc.description.sponsorshipThis work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.en_US
dc.formatMonograph
dc.format.mediumElectronic Resourceen_US
dc.language.isoen_US
dc.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dc.typeDissertation
dcterms.abstractThis dissertation presents variants on sorting and searching in external memory. In the first part of the dissertation, we derive lower and upper bounds on sorting with different-sized records. We show that the record size substantially affects the sorting complexity, and so does the final interleaving of the smaller and larger records in the final sorted sequence: sorting costs more when large and small records are segregated than when they are interleaved in the final sorted order. In the second part of the dissertation, we study the batched predecessor problem in external memory. Given the underlying sorted set S of size n, and a sorted query Q of size x <= n^c, 0 <= c < 1, we study tradeoffs between the searching cost, and the cost to preprocess S. We give lower bounds in three external memory models: the I/O comparison model, I/O pointer-machine model, and the indexability model. Our results show that in the I/O comparison model, the batched predecessor problem needs \Omega(\log_{B}n + 1/B) I/Os per element if the preprocessing is polynomial; with exponential preprocessing, the problem can be solved faster, in \Theta((\log_{2}n + 1)/B). In the third part of the dissertation, we introduce alternatives to the well-known Bloom filter data structure. The quotient filter is designed for RAM, but with better data locality than the Bloom filter. The buffered quotient filter and the cascade filter are SSD-optimized alternatives to the Bloom filter. In experiments, the cascade filter and buffered quotient filter performed insertions 8.6-11 times faster than the fastest Bloom filter variant and performed lookups 0.94-2.56 times faster.
dcterms.available2017-09-20T16:52:23Z
dcterms.contributorBender, Michael A.en_US
dcterms.contributorMitchell, Josephen_US
dcterms.contributorJohnson, Roberten_US
dcterms.contributorFarach-Colton, Martin.en_US
dcterms.creatorMedjedovic, Dzejla
dcterms.dateAccepted2017-09-20T16:52:23Z
dcterms.dateSubmitted2017-09-20T16:52:23Z
dcterms.descriptionDepartment of Computer Science.en_US
dcterms.extent83 pg.en_US
dcterms.formatApplication/PDFen_US
dcterms.formatMonograph
dcterms.identifierhttp://hdl.handle.net/11401/77297
dcterms.issued2014-12-01
dcterms.languageen_US
dcterms.provenanceMade available in DSpace on 2017-09-20T16:52:23Z (GMT). No. of bitstreams: 1 Medjedovic_grad.sunysb_0771E_11979.pdf: 1052653 bytes, checksum: e58c6f6a92f6eb2a585de2c8db636c07 (MD5) Previous issue date: 1en
dcterms.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dcterms.subjectComputer science
dcterms.subjectAlgorithms, Batched, External Memory, Lower Bounds, Searching, Sorting
dcterms.titleUpper and Lower Bounds on Sorting and Searching in External Memory
dcterms.typeDissertation


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