简介:TheMOSIXextensionstotheLinuxOperatingSystemallowthecreationofhigh-performanceLinuxFarmsandanexcellentintegrationoftheseveralCPUsoftheFarm,whosecomputationalpowercanbefurtherlyinereasedandmademoreeffectivebynetorkingthemwithintheGRIDenvironment.Followingthisstrategy,westartedtoperformcomputationaltestsusingtwoindependentfarrmswithintheGRIDenvironment.Inparticular,weperformedapreliminaryevaluationofthedistributedcomputingefficiencywithaMOSIXLinuxfarminthesimulationofgravitationalwavesdataanalysisfromcoalescingbinaries.Tothistask,twodifferenttechniqueswerecompared.theclassicalmatchedfilterstechniqueandoneofitspossibleevolutions,basedonaglobaloptimisationtechnique.
简介:Aneverincreasingnumberofcomputersystems-mainlyPCs-requireelaboratedmanagementstrategiesandtools.InthecontributiontoCHEP'01wewillpresentanddiscussnewconceptsanddevelopmentsconcerningdirectoryservicesandassetmanagement,Wewillinparticularreportonfirstexperienceswithsystemscurrentlybeingimplemented.
简介:CongestioncontrolforpacketssentonanetworkisimportantforDAQsystemsthatcontainaneventbuilderusingswitchingnetworktechnologies.QualityofService(QoS)isatechniqueforcongestioncontrol.RecentLinuxreleasesprovideQoSinthekerneltomanagenetworktraffic.Wehaveanalyzedthepacket-lossandpacketdistributionfortheeventbuilderprototypeoftheAtlasTDAQsystem.WeusedPC/LinuxwithGigabitEthernetnetworkasthetestbed.TheresultshowedthatQoSusingCBQandTBFeliminatedpacketlossonUDP/IPtransferwhiletheUDP/IPtransferinbesteffortmadelotsofpacketloss.TheresultalsoshowedthattheQoSoverheadwassmall.WeconcludedthatQoSonLinuxperformedefficientlyinTCP/IPandUDP/IPandwillhaveanimportantroleoftheAtlasTDAQsystem.
简介:TheZEUSexperimenthasmigrateditsreconstructionandanalysisfarmstoaPC-basedenvironment.Morethanoneyearofexperiencehasbeenacquiredwithsuccessfuloperationofananalysisfarmdesignedforseveralhundredusers.Speciallydesignedsoftwarehasbeenusedtoproveidefastandreliableaccesstolargeamountsofdata(30TBintotal),AftertheongoingupgradeoftheHERAluminosity,higherrequirementswillariseintermsofdatastoragecapacityandthroughputrate,Thenecessityofabiggerdiskcachehasledtoconsiderationofsolutionsbasedoncommoditytechnology,PC-basedfileserversarebeingtestedasacost-effectivestoragesystem,Inthisarticlewepresentthehardwareandsoftwaresolutionsdeplogyedanddiscusstheirperformance.scalabilityandmaintenanceissues.
简介:TheDAQhardwareoftheISTRA+experimentconsistsoftheVMEsystemcratethatcontainstwoPCI-VMEbridgesinterfacingtwoPC'swithVME,externalinterruptsreceiver,thereadoutcontrollerfordedicatedfront-endelectronics,theread-outcontrollerbuffermemorymodule,theVME-CAMACinterface,andadditionalcontrolmodules,TheDAQcomputingconsistof6PC'srunningtheLinuxoperatingsystemandlinkedintoLAN.ThefirstPCservestheexternalinterruptsandacquiresthedatafromfront-endelectronics,Thesecondoneistheslowcontrolcomputer.TheremainingPC'shostthemonitoringanddataanalysissoftware.TheLinuxbasedDAQsoftwareprovidestheexternalinterruptsprocssing,thedataacquisition,recording,anddistributionbetweenmonitoringanddataanalysistasksrunningatDAQPC's.Themonitoringprogramsarebasedontwopackagesfordatavisualization:home-writtenonandtheROOTsystem.MySQlisusedasaDAQdatabase.
简介:AnaffordablesolutiontoTier-3RegionalCenter(RC)ispresentedinthistalk,asimpleprototypehasbeensetupforevaluationofthesystemperformance,thisprototypecanbeeasilyscaledtobiggerone.Asetofmeasurementshavebeenconductedinbothcomputerandnetworksystembehavioursinmultipleconcurrentlyrunningjobscontexts.Inthetalkthesemeasuredresultsaretalkedanddiscussed,includingsystemandnetworkeffectiveutilizationsandlimitations,andtheidentifiedbottlenecksindifferentnetworklayouts,andthecomparisonswithsimulation.
简介:Thedolly+isaLinuxapplicationprogramtoclonefilesanddiskpartitionimagefromaPCtomanyothers.Byusingseveraltechniquessuchaslogicalringconnection,multithreadingandpipelining,itcouldachievehighperformanceandscalability.Forexample,intypicalcondition,installationstoahundredPCstakesalmostequivalenttimefortwoPCs.TogetherwiththeIntelPXEandtheRedHatkickstart,automaticandveryfastsysteminstallationandupgradingcouldbeperformed.
简介:根据机载光电平台的特点,建立了6个坐标系统,进行了8次线性变换,构建了从光电平台成像系统像面坐标系到大地地理坐标系的目标定位数学模型。计算了目标在大地地理坐标系的经纬度和高程坐标,分析了各种测量参数对目标定位精度的影响。通过建立误差模型和仿真数据进行目标定位实验,采用蒙特卡罗方法统计目标定位误差。实验结果表明,载机经纬度误差、载机姿态角度误差及光电平台指向角度误差是影响目标定位精度的主要因素,其中载机经纬度误差直接传递到目标定位误差,载机姿态角度误差和光电平台指向角度误差大体上以10-4~10-2比例作用到目标定位误差。本文方法有效可行,对机载光电平台目标定位具有实用价值。