计算机论文外文翻译

毕业设计（论文）英文翻译课题名称系部专业班级学号姓名指导教师2017年4月14日1PerformanceComparisonofPHPandJSPasServer-SideScriptingLanguagesMaterialSource:NotesinComputerScienceAuthor:ScottTrent;MichiakiTatsubori;ToyotaroSuzumura;AkihikoTozawaandTamiyaOnodera1IntroductionThedynamicscriptinglanguagePHP(PHPHypertextPreprocessor)hasbecomeenormouslypopularforimplementinglightweightwebapplications,andiswidelyusedtoaccessdatabasesandothermiddleware.ApachemodulepopularitysurveysperformedbySecuritySpaceinOctober2007indicatethat37%ofApacheservershavePHPsupportenabled,makingitthemostpopularApachemoduleby10percentagepoints.BusinessesarequicklyrealizingthepowerfulcombinationofaserviceorientedarchitectureenvironmentwithdynamicscriptinglanguageslikePHP.However,webelievethattherearestillcriticalperformanceissuesinvolvingPHPwhichremaintobeinvestigated.Thispaperfocusesontheuseofdynamicscriptinglanguagestoimplementwebserverfront-endinterfaces.ThiscorrespondswiththewaythattheindustrystandardwebserverperformancebenchmarkSPECweb2005utilizesPHPandJSP(JavaServerPages).Inthiscase,scriptsareusedfortheimplementationofdynamicpagegeneration,ratherthantherealizationofcomplexbusinesslogic.ThiscontrastswiththetraditionalusesofcomplexJSP-basedbusinesslogicimplementation.Whiletherearenumerousstudiesondynamicwebcontent,thispapercomplementsthesestudieswithdetailedanalysisfocusingonPHP.Forexample,followingtheperformancestudyonCGI(CommonGatewayInterface)basedwebserversfordynamiccontentbyYeager&McGrathbackin1995,researchersandpractitionershavebeenexaminingtheperformanceofmorerecentdynamicWebcontentgenerationtechnologies.Theseworks,however,handleapplicationscenarioswhereservletfront-endsimplementrelativelycomplexbusinesslogic.AlthoughWarnerandWorleydiscusstheimportanceofalsousingPHPwithSPECweb2005,tothebestoftheauthor’sknowledge,thispaperisthefirsttopublishadetailedanalysisofSPECweb2005experimentalresultsusingbothPHPandJSP.ThedetailedanalysisofPHPandJSPperformancebasedonSPECweb2005offeredbythispaperenablesdesignersandimplementersofwebserverstounderstandtherelativeperformanceandthroughputofdifferentversionsandconfigurationsofPHPandJSP.2017湖北汽车工业学院科技学院毕业设计（外文翻译）22Multi-tierWebServerArchitecture:LightweightFront-EndUsingPHP/JSPDeveloperstypicallyusePHPtoimplementafront-endinterfacetodynamicWebcontentgenerators,whicharecombinedwithwebserversoftwareandback-endserverstoprovidedynamiccontent.Thewebserverdirectlyhandlesrequestsforstaticcontentandforwardsrequestsfordynamiccontenttothedynamiccontentgenerator.Thedynamiccontentgenerator,supportedbyback-endservers,executescodewhichrealizesthebusinesslogicofawebsiteandstoresdynamicstate.Back-endserversmaybeimplementedasastraight-forwarddatabase,ormaybemorecomplexservershandlingthebusinesslogicofthewebsite.Thefront-endimplementationmayvaryfromheavy-weightbusinesslogichandlerstolightweightclientscomposingcontentreceivedfromback-endservers.Thispaperfocusesonmulti-tierwebsitedevelopmentscenariosutilizingsuchlightweightfront-ends,supportedbyoneormorelayersofheavy-weightback-ends.ThisassumptionisreasonablewhenconsideringService-OrientedenvironmentswherePHPscriptsareusedtoimplementamash-upofservicesprovidedelsewhere,inadditiontothecaseofsimplewebsitessuchasbulletinboardswherePHPscriptsarejustawrappertoadatabase.Withinthescenariosdescribedinthispaper,thedynamiccontentgeneratorprovidesclientimplementationinadditiontopagecomposition.Itconnectstotheback-endserverthroughanetworkusingeitherstandardprotocolssuchasHTTPorapplication/middleware-specificprotocols.JSPtechnologycanbeconsideredanalternativetoPHPinimplementingsuchfront-ends.WhileitispartoftheJavaServletframework,developerstypicallyuseJSPtoimplementlightweightfront-ends.BothPHPandJSPallowdeveloperstowriteHTMLembeddedcode.Infact,althoughtherearelanguageinherentdifferencesbetweenPHPandJava,theuseofPHPscriptsandJSPfilescanbeverysimilar.Theobjectiveoftheexperimentsdetailedinthispaperistomeasuretheperformanceoflightweightfront-enddynamiccontentgenerationwritteninPHPandJSPwithpopularwebserverssuchasApacheandLighttpd.ThiswebserverarchitecturescenarioinvolvesuserswhoaccessawebserverwithpageswritteninplainstaticHTML,aswellasJSPandPHPscriptswhichmixscriptinglanguagewithHTMLcode.Theconfigurationassumedwithinthepaperisatypicalone,wherewebserversoftware,suchasApache,distinguishesbetweenpureHTML,JSP,andPHPrespectivelywithsuffixessuchas.html,.jsp,and.php.HTMLcodeisdirectlyreturnedtotherequestingend-user’swebbrowser,whereJSPandPHPpages2017湖北汽车工业学院科技学院毕业设计（外文翻译）3arerespectivelyparsedbytheTomcatscriptengineandthePHPruntimeenginewhichbothprovidepureHTMLwhichisforwardedtotheend-useronaremotesystem.AcommonpointbetweenJSPandPHPisthatimplementationswhichperformwellhaveadynamicallycompiledandcachedbytecode.Forexample,theJavaruntimeusedbytheTomcatscriptenginewhichweusedperformsmuchbetterwhentheJust-in-Time(JIT)compilerisenabledtocreateefficientcachednativeruntimecode.Similarly,theZendPHPruntimeweusedalsoperformssignificantlybetterwhentheAlternativePHPCache(APC)isenabled,inwhichAPCstoresPHPbytecodescompiledfromthescriptsource