内容课件讲稿sun microsystems henry fong

5thEuropeanLS-DYNAUsersConference

ComputingTechnology(2)

5thEuropeanLS-DYNAUsersConference

ComputingTechnology(2)

7a-13

7a-13

InadditiontoofferingSPARC/SolarissystemsforMCAEusers,SunMicrosystemsalsomarketsOpteron-basedserversandworkstations.TheseOpteronsolutionsofferexcellentprice/performanceforLS-DYNAsimulations,andareparticularlysuitableforclustering.Usershaveachoiceofthreeoperatingsystems:Solaris10x64;Linux(SuSEorRedHat);orWindows.Thispaperdescribesbrieflythesecomputingsystems,andshowsometypicalLS-DYNAperformancesonstandardbenarkssuchthe3-car-crashproblem.AlsocitedisaMefoscoldrollingbenark,runusingbothaSPARC/SolarisSunFireV480serveraswellasaclusterofSunLX50Xeon-basedprocessors.Sun'sclustersystemstypicallyutilizeSun'sN1GEgridengineloadmanagementsoftwaretoschedule,manage,andprioritizecomputejobs.

GRID-BASEDVIRTUALPROTOTYSIMULATIONINMCAE

Numericalsimulationofreal-worldproblemshas estandardpracticeamongmanufacturersworldwide,allowingthemtoreducecosts,meetshorttime-to-marketwindowswhileimprovingproductquality,optimizingmaterialsusage,andaddressingincreasinglystringenternmentalsafetyandenvironmentregulations.ThistypeofsimulationiscalledMCAE(mechanicalcompuidedengineering),orsometimesVirtualProductDevelopment(VPD),andtypicallyusefiniteelementysis(FEA)methods.WithSun'sGridComputing,thelatestAMDOpteronprocessor-basedserversandworkstations,SundeliveroutstandingperformanceandscalabilityforMCAE/VPDapplications,allowingmanufactures(automotive,aerospace,consumergoods,biomedical,etc.)toproducebetndsaferproductsataffordablecosts.

THEMEFOSCOLDROLLINGBENARK

ThemodelusedinthisMefosbenarkisusedforsimulationofthecoldrollingprocess.Duetosymmetry,onlyhalftheupperrollandaquarterofthestripareyzed.Therollisrotatingwithaperipheralvelocityof6.0m/sattheouterradius.Thestripinthemodelis2.4mlong,3.0mmthick,and1.0mwidebeforetherolling.Thismodellengthisprobablylargeenoughtoreachthesteady-stateconditionwhichprevailsinthecentralpartoftherealstrip,whichismuchlongerinreality.Theouterdiameteroftheworkrollis62.35mm,andthegapbetweentheworkrollsis2.6mmbeforerolling.Theworkrollismodeledasarigidsurface.Thereisabackandfronttensionappliedtothestripof235and300MPa,respectively.Thedensityofthematerialsis25timeslargerthantherealdensityforsteel,inordertospeedupthecalculations.Thefiniteelementmodelhas1,662,202nodesand580,000solidelements.

Therollingprocesstakesabout0.4seconds.Itisfoundthatthereisasteady-stateconditionrelativetotherollingsection,prevailingfromabout0.12to0.28seconds.Inthebenark,thesimulationtimeis0.01second.Therefore,theexecutiontimeofafullLS-DYNArunisapproximay30timeslongerthantheoneinthebenark.

ThefrictionalongtheslidelinebetweentherollsandtheteismodeledasCoulombfriction.Thefrictioncoefficientisassumedtobe0.07withlubricatedrolls.Young'smodulusforthetematerialisassumedtobe206GPa,andPoisson'sratioissetto0.3.TheyieldcriterionusedisvonMisesandtheassociatedflowruleisused.Variableisotropichardeningisassumed.Theeffectivestress-effectivesticstrainrelationisgivenfromlinearinterpolationbetweenthevaluesinthefollowingtable:

Strain EffectiveStress(MPa)

0.00000

9.1000+8

0.15415

1.0100+9

0.27820

1.1330+9

0.44183

1.1660+9

Thematerialisnotverystrainratesensitive.

ThisMefoscoldrollingbenarkhasbeenrunusingthreeSunsystemsthatuseSPARC/SolarisorLinux:

Clusterof16SunFireLX50–Xeon-based,withcoppergigabitEthernet

SunFire6800servers

Clusterof32SunFireV480's–Myrinetinterconnect

AllthesesystemsshowedimpressiveLS-DYNAscalabilityonthisMefoscoldrollingbenark.

Thebenarkresultsaresummarizedbelow:

SunLX50Cluster(Xeon-based),1cpupersystem

#CPU'sTotalSecondsEfficiency

1

63,130

1.0

2

32,540

0.97

4

16,286

0.97

8

9,597

0.82

12

5,925

0.89

16

5,004

0.79

SunLX50Cluster,2cpu'spersystem

4

21,560

0.67

8

12,655

0,62

12

8,482

0.62

16

6,872

0.57

24

4,816

0.55

32

3,760

0.53

SunFire6800SMP-server,24x1,200MHz

#CPU'sTotalSecondsEfficiency

4

19,771

0.89

8

10,557

0.83

12

6,684

0.87

24

3,259

0.89

SunFireV480Cluster,Myrinetinterconnect

32(6x2) 2,400 0.91

128(32x4)747 0.73

NotethatontheSunFire6800server,thebenarkwasneverrunon1cpu.Theefficiencyfigurefor4cpu'swastakenonaSunFire6800server,24x900MHz,andthenassumedtobethesamefor4cpu'sontheSunFire6800,24x1,200MHzsystem.Therestoftheefficiencynumbersforthissystemarecalculatedusingthisassumption.Thesameistruefortheclusterof32SunFire480'sthatusethesameCPU'sastheSunFire680024x1,200MHzsystem.Here,wearealsoassumingthatsingleCPUperformanceontheSunFire6800,24x1,200MHzandtheSunFireV480isidentical.

Inthiample,LS-DYNAscalesverywell,evenupto128cpu's.Ofcourse,thisexcellentscalabilitymaybeduetothesimplicityofthemodel.But,themodelcomesfromreal-worldcoldrollingapplications,andthebenarkwasnotdesignedwithscalabilityinmind.Thereismaysimilaritieswiththemodelpresentedin[1]thathasbeenusedforsimulationofthehotrollingprocess.Itisalsonoteworthythatanumberofdifferentpositionstrategieshavebeentried.Noneoftheresults,however,gaveanyrealsignificantimprovementoverthedefaultoneshowninthetablesabove.TheresultsclearlyshowedthatLS-DYNAcanbeusedinalargeclusterwithoutsufferingtoomuchfromparalleloverhead,providedthatthemodelitselfdoesnotintroduceanyloadimbalances.

SUN'SOPTERON-BASEDSERVERSANDWORKSTATIONS

SunMicrosystemsmarketsafamilyofAMDOpteron-basedlow-endserversandworkstations:

SunFireV20zserver,upto2Opteron200seriesprocessors,upto16GBmemory

SunFireV40zserver,upto4Opteron800seriesprocessors,upto32GBmemory

SunJavaWorkstationW1100z,1Opteron100seriesprocessor,upto8GBmemory

SunJavaWorkstationW2100z,2Opteron200seriesprocessors,upto16GBmemory

UsingthelatestAMDOpteronprocessors,thesesystemsofferoutstandingperformance,atcompetitiveprices,onalltheleadingMCAEandMCADapplications.TheyareespeciallyattractiveforManufacturing/MCAEorganizations,becausebenefitsinclude:

Largememorycapacityforcomplexmodelsanddatasets

High-speed3Dgraphicsforpre-andpost-processing

ChoiceofSolaris10operatingsystem,Linux,orWindows

64-bitsystemsdesignedforhighperformance,withexcellentscalability

and32-bitcompatibility.

RackedclustersmaybeassembledusingtheseSunFireV20zandV40zservers,inconfigurationsof8-,16-,and32-cpu's.Variousinterconnectoptionsareavailable:gigabitEthernet; /Myrinet;orInfiniband(Topspin,Voltaire,InfiniCon,etc.).Sun'sN1GEGridEnginesoftwareisusedforloadmanagement,toefficientlydistributecrash,metalforming,ordropimpactworkloadstotheavailablecomputingresourcesinanorganization.Sun'sCRS(CustomerReadySystems)organizationisavailabletohelpcustomersassembledesiredconfigurations.

LS-DYNAPERFORMANCEON3-CAR-CRASHBENARK

Sun'sOpteron-basedserversoffergoodfloatingpointperformanceandlargememorysupport.ClustersofthesesystemswillprovideusercellentscalabilityoncodessuchasLS-DYNA.Thefollowingtypical3-car-crashbenark(carmodelsfromFHWA/NHTSANationalCrashysisCentGeorgeWashingtonUniversity–benarkfrom ,developedbyProfessorDavidBensonofUniversityofCaliforniaatSanDiego)showsthefollowingresultsonSun'sclusterofV20zOpteron-basedservers[2004]:

--------------------------------------------------------------------------------------

CPU'sElapsedTime(hrs:min)Scalability Efficiency(%)

1

79:04

1.00

100.0

2

41:14

1.92

96.0

4

20:37

3.83

95.8

8

12:07

6.52

81.5

16

5:56

13.3

83.1

24

4:40

16.9

70.4

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TheseresultswereobtainedusingaSunFireV20zMyrinetcluster(AMDOpteron248,2.2GHz),SuSELinux,inApril2004.ThelatestAMDOpteronprocessorisat2.6GHz,andweexpecttheLS-DYNAresultstoscaleandimproveaccordingly.The3-car-crashmodelciteduses794,078elements,andthesimulationtimewas150msec.ThemodelwasdevelopedbyLSTC'sMikeBurgerandProfessorDavidBensonofUCSD.

LS-DYNAscalabilityicellentonthis3-car-crashbenarkupto16cpu's,andfairlygoodevenat24cpu's.Comparingelapsedtimes,theseOpteronclusterresultsareequaltoorbetterthanotherclustersystemswithcompetitiveprocessors–atsignificantlylowercost.

GRIDCOMPUTINGINMANUFACTURING

Withincreasinglycomplexdesignsandgloballydispersedoperations,manufacturersinvirtuallyallindustriesneedeffectivecomputationaltoolstofacilitatecollaborationofmultipleteams,partners,andrs–whilegettingthemostfromtheircomputationalresources.GridComputingtechnologycanhelpbyallowingdisparatesystemstobepooledandmanagedasacommoncomputingresource.Inparticular,MCAEusersbenefitfromincreasedaccess(e.g.,usingaSunN1GE-basedportal)tocomputationalresources,whileotherdesignteamsandpartnersgetjusttheinformationtheyneed.Ultimay,GridComputingwillhelpimproveinnovation,providingtheresourcesasneededtogethigh-qualityproductstomarketquicker,whilereducingcostsandprovidingarapidreturnoninvestment.Tothisgoal,SunMicrosystemsrecentlyannouncedaUtilityComputinginitiative,whereseverallargedenters,eachofferingthousandstotensofthousandsofcpu's,canbeaccessedbycustomerstosatisfytheircomputingrequirements,onapay-as-you-gobasis.Thesedatacentersareinitiallytargetedatverticalmarketssuch