NASA Technical Reports Server (NTRS) 20020039063: Beyond the NAS Parallel Benchmarks: Measuring Dynamic Program Performance and Grid Computing Applications

4 Pages·0.1 MB·English

by  NASA Technical Reports Server (NTRS)

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Contents
Beyond the NAS Parallel Benchmarks:
Heasurlng Dynamic Program Performance
1. AbriefhistoryofNPB
and Grid Computing Applications
2. Whatis(not) beingmeasuredbyNPB?
3. Irregulardynamicapplications(UABenchmark)
RobF.Vanderwljngaart (ComputerSciencesCorp.)
4. Wideareadistributedcomputing(NASGrid
Benchmarks- NGB)
RupakBlswas,HlchaeJFmmkin (NASDivision)
HuiyuFeng(GeorgeWashingtonUnlve_)
NASAAmesResearchCenter
Hoffett Reld,CA
I
A Brief History of NPB A Brief History of NPB (_cont'd)
Goal: Peasureperformanceofmodern(parallel) • EP Random-numbergeneral_
architecturesrunningscientificapps
• IS Integer sort
Contents: 5 kernels,3pseudoappa(implicitCFD) •CG Conjugategradient
• HG HultJgddmethodforPoissioneqn
Approach:NPBI: Paper-and-pencilspecs
NPB2:Sourcecodeimplemental_ons • FT SpectTalmethod(FFT)forLaplaceeqn
(F77/C/HPX)
PBN: Sourcecodeimplementations
(HPF/OpenHP/.lava) Pseudo • BT ADI; Block-Tridiagonalsystems
apps:
• SP ADI; ScalarPentadiagonalsystems
• LU Lower-UppersymmetricGauss-Seidel
J
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What istested inNPB2? What isnottested inNPB2?
_Name Network •_jmamica_ changing memory ao:esses "t
funct_ns bmdvddth tatmcy I_lrw_ctth cache
UA
•Zrregula_r ao:esses )
,EP v" •False shadng / cache coherence costs
IS ¢" ,/
CG
• System soitware I Grid computing middleware _1
fh'G
•Fault tolerance NGB
'FT ]
•Wlde area(public)networkbandwidth/latency
v'
SP
UJ
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Un_red AdaptiveMeshRefinement(UA} UA (cont'd)
QSkuctured, static grids -_ fixed-static memory access Differentkindsoftriangularrefinement
QMessage passing -, private address spaces
Choice of parallelizat_on paradigm not (very)important
Unsb'uctured, adaptive mesh refinement (Btswas, Ofiker)
• No solver - only refine, (re)partilt_, and remap
•Implementations:
>MPI - SGI Origin, CrayT3E
>OpenMP - SGI Origin
>MultJthreading - Tera (Cray) MTA
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UA _cont'd) UA (cont'd)
Overviewof PLUM Overallassessment
Code _no_ S_/ab#/ty Po_ab#/ty
Parad/gm it_mase increase
MPI 100% 70% Medium High
OpenMP 10% 5% None Medium
Mul_-
threading 2% 7% High Low
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UA (cont'd) UA(cont'd)
Complete,practically usefulbenchmark: Flamepm_gaUon problem(Feng&Mavfiplis):
•Includessolver •Scalarb'ansportecln: _ +V.VT=_AT-e-_F(T)
•Is 3-dimensional •Vekx_tyfield given:linearproblem
•DoescoarseninginaddilJonto refinement • Rectangulardomain
•SpendslittleUmeon(re)parl_ioning/(re)mapping • Rectangularnonconformingelements
•Is wellloadbalanced •Speclzalelementsofrelativelyhigh order(5_)
•Requiresnodatafiles •Mixede_cplictt/impliciUtmeintegration
•Is compact:NPB2apps~ S,000lines(SP,BT,LU) •Spatialrefinement/coarsening
•Interface opscheapc_mparedtooverallscheme
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UA (cont'd) N/kS Grid Benchmarks (NGB)
_ _ 3,__,veiofrefinement
(hot) (Cl_
Goal: Heasureperformanceofmoderndistributed
systems,emphasizing GridcompuUng,
Alsogaugesfunctionality.
Contents: 4 compoundtasks:3 pseudoapps(implicit
CFD),2_, allfromNPB2.
Approach:NGBI: Palx_'-and-pendlspecs.
NGB2:Sourcecodeimplementations
(NPB2/PBN+
Globus/L_ion/Corba/Condor/Java ...)
Rame --_
J J
NGB coned NGB cont'd
Must define boundaries because: •ProvidesyntheticGridapp.forscientificcomputing:
•Gridconcept/environment/infrastructurenotwetldefined ,_dataflowgraphcoupling NPBcodes
•Gddhasverymanysoftware/hardwarecomponents •Specify:
•Gridhascomplex functk_nalhierarchy ;_abstractsewioesneoessafy
•Gridisatime/organization/applicationdependenttarget _,problemsizes(classes):S,W, A,B.C
Cannot freeze benchmark Implementation because: •Donotspecify:
• NoclearGridenvironmentwinner ;,-fauRrecoveryreqs
•Nodear pictureofrepresentativeGridapplication securityreqs
•Measureandreportturnaroundtime