简介:Theobject-orientedtagdatabaseoftheZEUSexperimentatHERAisbasedonObjectivity/DB.Itisusedtorapidlyselecteventsforphysicsanalysisbasedonintuitivephysicalcriteria.Thetotalnumberofeventscurrentlyinthedatabaseexceeds150millionBasedonthedetectorconfigurationdifferentinformationcanbestoredforeachevent.Anewversionofthedatabasesoftwarewasrecentlyreleasedwhichservesclientsonamultitudeofbatchmachines,workgroupserversanddesktopmachinesrunningIrix,LinuxandSolaris.ThisreplacesanearlierversionwhichwasrestrictedtothreeSGImachinesMultiplecopiesofthedatacanbestoredtransparentlytotheusersforexampleifanewofflinereconstructionofthedataisinprogress.Areportisgivenontheupgradeofthedatabaseanditssuperiorperformancecomparedtotheoldeventselectionmethod.
简介:TheZEUSexperimenthasmigrateditsreconstructionandanalysisfarmstoaPC-basedenvironment.Morethanoneyearofexperiencehasbeenacquiredwithsuccessfuloperationofananalysisfarmdesignedforseveralhundredusers.Speciallydesignedsoftwarehasbeenusedtoproveidefastandreliableaccesstolargeamountsofdata(30TBintotal),AftertheongoingupgradeoftheHERAluminosity,higherrequirementswillariseintermsofdatastoragecapacityandthroughputrate,Thenecessityofabiggerdiskcachehasledtoconsiderationofsolutionsbasedoncommoditytechnology,PC-basedfileserversarebeingtestedasacost-effectivestoragesystem,Inthisarticlewepresentthehardwareandsoftwaresolutionsdeplogyedanddiscusstheirperformance.scalabilityandmaintenanceissues.