全文搜索引擎的设计与实现-外文翻译

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1、江汉大学毕业论文（设计）外文翻译原文来源TheHadoopDistributedFileSystem:ArchitectureandDesign中文译文Hadoop分布式文件系统：架构和设计姓名XXXX学号72013年4月8日英文原文TheHadoopDistributedFileSystem:ArchitectureandDesignSource：http://hadoop.apache.org/docs/r0.18.3/hdfs_design.htmlIntroductionTheHadoopDistributedFileSystem(HDFS)isadistributedfile

2、systemdesignedtorunoncommodityhardware.Ithasmanysimilaritieswithexistingdistributedfilesystems.However,thedifferencesfromotherdistributedfilesystemsaresignificant.HDFSishighlyfault-tolerantandisdesignedtobedeployedonlow-costhardware.HDFSprovideshighthroughputaccesstoapplicationdataandissuitablef

3、orapplicationsthathavelargedatasets.HDFSrelaxesafewPOSIXrequirementstoenablestreamingaccesstofilesystemdata.HDFSwasoriginallybuiltasinfrastructurefortheApacheNutchwebsearchengineproject.HDFSispartoftheApacheHadoopCoreproject.TheprojectURLishttp://hadoop.apache.org/core/.AssumptionsandGoalsHardwa

4、reFailureHardwarefailureisthenormratherthantheexception.AnHDFSinstancemayconsistofhundredsorthousandsofservermachines,eachstoringpartofthefilesystem’sdata.Thefactthatthereareahugenumberofcomponentsandthateachcomponenthasanon-trivialprobabilityoffailuremeansthatsomecomponentofHDFSisalwaysnon-func

5、tional.Therefore,detectionoffaultsandquick,automaticrecoveryfromthemisacorearchitecturalgoalofHDFS.StreamingDataAccessApplicationsthatrunonHDFSneedstreamingaccesstotheirdatasets.Theyarenotgeneralpurposeapplicationsthattypicallyrunongeneralpurposefilesystems.HDFSisdesignedmoreforbatchprocessingra

6、therthaninteractiveusebyusers.Theemphasisisonhighthroughputofdataaccessratherthanlowlatencyofdataaccess.POSIXimposesmanyhardrequirementsthatarenotneededforapplicationsthataretargetedforHDFS.POSIXsemanticsinafewkeyareashasbeentradedtoincreasedatathroughputrates.LargeDataSetsApplicationsthatrunonH

7、DFShavelargedatasets.AtypicalfileinHDFSisgigabytestoterabytesinsize.Thus,HDFSistunedtosupportlargefiles.Itshouldprovidehighaggregatedatabandwidthandscaletohundredsofnodesinasinglecluster.Itshouldsupporttensofmillionsoffilesi