AI 系统 快速入门

AISystem

NSCCTraining17December2020

NSCCAISystem

PAGE

10

Expectations

TheDGX-1nodesaremostsuitedtolarge,batchworkloads

e.g.trainingcomplexmodelswithlargedatasets

Weencourageuserstododevelopmentandpreliminarytestingonlocalresources

UsersareencouragedtousetheoptimizedNVIDIAGPUCloudDockerimages

Utilisation

AccessisthroughPBSjobscheduler

Weencourageworkloadswhichcanscaleuptoutiliseall8GPUsonanodeorrunacrossmultiplenodes

Userscanrequestfewerthan8GPUs

MultiplejobswillthenrunonanodewithGPUresourceisolation(usingcgroups)

YouwillonlyseethenumberofGPUsyourequest

SystemOverview

LoginNodes

DGX-1Nodes

InfiniBandNetwork

PBSJob

Scheduler

Storage

NSCCVPN:aspire.nscc.sg

Externaloutgoingaccess

astar.nscc.sg

Externaloutgoingaccess

ntu.nscc.sgNointernetaccess

NSCCNetworks

nscc0[3-4]

OnNUSandNTUloginnodes:

nscc0[1-2]

Forexternaloutgoingaccess:

sshnscc04-ib0

ntu0[1-4]

nus0[1-4]

nus.nscc.sg

Nointernetaccess

dgx410[1-6]

Nodirectincomingaccess

Externaloutgoingaccess

ProjectID

ProjectIDsprovideaccesstocomputationalresourcesandprojectstorage.

AIprojectsareinGPUhours

OnlyAIprojectcodescanwillrunonthedgxqueues

Inthefollowingmaterialwhereyousee

$PROJECTreplacewiththecodeforyourproject,forexamplethestakeholderpilotprojectcodewas41000001

Filesystems

TherearemultiplefilesystemsavailableontheNSCCsystems

/home GPFSfilesystemexportedtotheDGXnodesasanNFSfilesystem

/scratch high-performanceLustrefilesystem

/raid LocalSSDfilesystemoneachontheDGXnodes

I/OintensiveworkloadsshoulduseeithertheLustre/scratchfilesytemorthelocalSSD/raid

filesystem

VisibleonLoginnodes

VisibleonDGXhostO/S

VisibleinDGXincontainers

Description

/home/users/ORG/USER

YES

YES

YES

Homedirectory:$HOME50GBlimit

/home/projects/$PROJECT

YES

YES

YES

ProjectdirectoryLargerstoragelimits

/scratch/users/ORG/USER

YES

YES

YES

HighperformanceLustrefilesystem.Softlinkedto$HOME/scratch

Noquota,willbepurgedwhenfilesystemisfull.

/raid/users/ORG/USER

NO

YES

YES

LocalSSDfilesytemoneachDGXnode.

7TBfilesystemonvisibleonthatspecificnode.Noquota,willbepurgedwhenfilesystemisfull.

Filesystems

The/homefilesystem(homeandprojectdirectories)ismountedandvisibleonallloginandDGXnodesandinsideDockercontainers.Thisfilesystemshouldbeusedforstoringjobscripts,logsandarchivalofinactivedatasets.ActivedatasetswhicharebeingusedincalculationsshouldbeplacedoneithertheLustre/scratchfilesystemorthelocalSSD/raidfilesystems.

IntensiveI/OworkloadsonlargedatasetsshouldusetheLustrefilesytem.TheLustre/scratchdirectoryisnowmounteddirectlyontheDGXnodesandautomaticallymountedinsideDockercontainers(previouslyitwasonlyvisibleonloginnodesandmountedinDockercontainers)

ThelocalSSD/raidfilesystemisfastbutonlyvisibleonaspecificDGXnode.Thiscanbeused

fortemporaryfilesduringarunorforstaticlong-termdatasets.

Datasetswithverylargenumbersofsmallfiles(e.g.100,000fileswhichareapprox.1kBin

size)MUSTusethelocalSSD(/raid)filesystemorLustre(/scratch)filesystem.

Networkfilesystems(/home&/scratch)arenotsuitedtodatasetswhichhaveverylargenumberofsmallfilesbecausemetadataoperationsonnetworkfilesystemsareslow.

PBSQueueConfiguration

User

queues

Execution

dgx-dev

dgx-03g-04h

dgx-03g-24h

dgx-48g-04h

dgx-48g-24h

dgx

queues

…

Per-userrunlimits,per-queuerunlimitsandnodeassignmentusedtocontrolutilisation

Shorterqueues

havehigherpriority

Halfofanodeforsharedinteractivetesting&development

TypicalPBSNodeConfiguration

dgx-48g-*

dgx-03g-*

dgx-dev

dgx4101

dgx4102

dgx4103

dgx4104

dgx4105

()

()

dgx4106(4GPUS)

dgx4106(4GPUS)

Differentqueuescanaccessdifferentsetsofnodes

Shorterqueueshavebeengivenhigherpriority

Queuelimitsonthe48hourqueueareverystrictsowaittimesinthatqueueareextremelylong(throughputismuchbetterinthe4hourand24hourqueues)

Configurationmaybechangedtomatchrequirementsbasedontheloadinthe

queues

InteractiveUse–Access

SharedaccesstohalfofaDGXnode(4GPUs)isavailablefortestingofworkflowsbeforesubmissiontothebatchqueues

Toopenaninteractivesessionusethefollowingqsubcommandfromaloginnode:

user@nscc:~$qsub-I-qdgx-dev-lwalltime=8:00:00–P$PROJECT

#$PROJECT=41000001or22270170

Resourcesaresharedbetweenallusers,checkactivitybeforeuse

Usageofthedgx-devqueueisnotchargedagainstyourprojectquota

InteractiveUse–Docker

TorunaninteractivesessioninaDockercontainerthenaddthe“-t”flagtothe“nscc-dockerrun”command:

user@dgx:~$nscc-dockerrun-tnvcr.io/nvidia/tensorflow:latest

$ls

README.mddocker-examplesnvidia-examples

$tty

/dev/pts/0

The–tflagwillcausejobtofailifusedinabatchscript,onlyuseforinteractiveuse:

user@dgx:~$echotty|nscc-dockerrun-tnvcr.io/nvidia/tensorflow:latest

theinputdeviceisnotaTTY

Batchscheduler

Accessingthebatchschedulergenerallyinvolves3commands:

Submittingajob: qsub

Queryingthestatusofajob: qstat

Killingajob: qdel

qsubjob.pbs #submitaPBSjobscripttoscheduler

qstat #querythestatusofyourjobsqdel11111.wlm01#terminatejobwithid11111.wlm01

See

https://help.nscc.sg/user-guide/

formoreinformationonhowtousethePBSscheduler

Introductoryworkshopsareheldregularly,moreinformationat

https://www.nscc.sg/hpc-calendar/

ExamplePBSJobScript(Headers)

#!/bin/sh

##Lineswhichstartwith#PBSaredirectivesforthescheduler

##Directivesinjobscriptsaresupercededbycommandlineoptionspassedtoqsub

##Thefollowinglinerequeststheresourcesfor1DGXnode#PBS-lselect=1:ncpus=40:ngpus=8

##Runfor1hour,modifyasrequired

#PBS-lwalltime=1:00:00

##SubmittocorrectqueueforDGXaccess

#PBS–qdgx

##SpecifyprojectID

#Replace$PROJECTwithProjectIDsuchas41000001or22270170

#PBS-P$PROJECT

##Jobname#PBS-Nmxnet

##MergestandardoutputanderrorfromPBSscript#PBS-joe

ExamplePBSScript(Commmands)

#Changetodirectorywherejobwassubmitted

cd"$PBS_O_WORKDIR"||exit$?

#SpecifywhichDockerimagetouseforcontainer

image="nvcr.io/nvidia/tensorflow:latest"

#Passthecommandsthatyouwishtoruninsidethecontainertothestandardinputof“nscc-dockerrun”

nscc-dockerrun$image<stdin>stdout.$PBS_JOBID2>stderr.$PBS_JOBID

Hands-on

/home/projects/ai/examples

ExamplePBSjobscriptstodemonstratehowto:

submitajobtorunonaDGX-1node

startacontainer

runastandardMXNettrainingjob

installapythonpackageinsideinacontainer

See

https://help.nscc.sg/user-guide/

formoreinformationonhowto

usetheNSCCsystems

Hands-on

Step1:LogontoNSCCmachine

Step2:Runthefollowingcommandsandconfirmthattheywork:

cp-a/home/projects/ai/examples.#submitfirstbasicexample

cdexamples/1-basic-job&&\qsubsubmit.pbs

#runatrainingjob

cd../../examples/2-mxnet-training&&\qsubtrain.pbs

#installapythonpackageinsidecontainer

cd../../examples/3-pip-install&&\

qsubpip.pbs

Useqstattocheckjobstatusandwhenjobshavefinishedexamineoutputfilestoconfirm

everythingisworkingcorrectly

PartialNodeJobSubmission

Specifyrequiredngpusresourceinjobscript:

#PBS-lselect=1:ngpus=N:ncpus=5N

whereNisthenumberofGPUsrequired

e.g.“-lselect=1:ngpus=4:ncpus=20”

$echonvidia-smi|qsub-lselect=1:ncpus=5:ngpus=1-lwalltime=0:05:00-qfj5-P410000017590401.wlm01

$grepTeslaSTDIN.o7590401

| 0TeslaV100-SXM2...On |00000000:07:00.0Off| 0|

$echonvidia-smi|qsub-lselect=1:ncpus=10:ngpus=2-lwalltime=0:05:00-qfj5-P41000001

7590404.wlm01

$

grep

Tesla

STDIN.o7590404

|

0

Tesla

V100-SXM2...On

|00000000:07:00.0Off|

0|

|

1

Tesla

V100-SXM2...On

|00000000:0A:00.0Off|

0|

$echonvidia-smi|qsub-lselect=1:ncpus=20:ngpus=4-lwalltime=0:05:00-qfj5-P410000017590408.wlm01

$

grep

Tesla

STDIN.o7590408

|

0

Tesla

V100-SXM2...

On

|

00000000:07:00.0

Off

|

0

|

|

1

Tesla

V100-SXM2...

On

|

00000000:0A:00.0

Off

|

0

|

|

2

Tesla

V100-SXM2...

On

|

00000000:0B:00.0

Off

|

0

|

|

3

Tesla

V100-SXM2...

On

|

00000000:85:00.0

Off

|

0

|

NOTETHATTHEINTERACTIVEQUEUE(dgx-dev)WILLSTILLGIVESHAREDACCESSTOASETOFGPUSONTHETEST&DEVNODE

Checkingwhereajobisrunning

4availableoptionstoseewhichhostajobisrunningon:

$qstat-fJOBID

JobId:7008432.wlm01

<snip>

comment=JobrunatWedMay30at13:25on(dgx4106:ncpus=40:ngpus=8)

<snip>

$qstat-wanJOBID

wlm01:

Req'dReq'd Elap

JobID Username Queue Jobname SessID NDSTSK MemoryTimeSTime

-7008432.wlm01 fsg3 fj5 STDIN 67452 1 40 --01:00R00:05:09

dgx4106/0*40

$pbsnodes-Sjdgx410{1..6}

vnode

state

njobs

run

susp

mem

f/t

ncpus

f/t

nmics

f/t

ngpus

f/t

jobs

dgx4101

free

0

0

0

504gb/504gb

40/40

0/0

8/8

--

dgx4102

free

0

0

0

504gb/504gb

40/40

0/0

8/8

--

dgx4103

free

0

0

0

504gb/504gb

40/40

0/0

8/8

--

dgx4104

free

0

0

0

504gb/504gb

40/40

0/0

8/8

--

dgx4105

free

0

0

0

504gb/504gb

40/40

0/0

8/8

--

dgx4106

job-busy

1

1

0

504gb/504gb

0/40

0/0

0/8

7008432

$gstat

-dgx

#similarinformationtoabovecommandsbutshowsinformationonjobsfromallusersandiscachedsohas

aquickerresponse(butdatamaybeupto5minutesold)

AttachingsshSessiontoPBSJob

Ifyousshtoanodewhereyouarerunningajobthenthesshsessionwillbeattachedtothecgroupforyourjob.

Ifyouhavemultiplejobsrunningonanodeyoucanselectwhichjobtobeattachedtowiththecommand“pbs-attach”

$pbs-attach-l #listavailablejobs

7590741.wlm017590751.wlm01

$pbs-attach7590751.wlm01

executing:cgclassify-gdevices:/7590751.wlm0143840

Availableworkflows

Dockercontainers(recommended)

OptimizedDLframeworksfromNVIDIAGPUCloud(fullysupported)

Singularitycontainers(besteffortsupport)

https://sylabs.io/docs/

Applicationsinstalledbyuserinhomedirectory(e.g.Anaconda)(besteffortsupport)

DockerImages

The“nscc-dockerimages"commandshowsallimagescurrentlyinrepository

Currentlyinstalledincludes:

nvcr.io/nvidia/{pytorch,tensorflow,mxnet}:*

nvcr.io/nvidia/cuda:*

Olderimageswillberemovediftheyhavenotbeenusedrecently,ifyouneedaspecificversionthenitcanbepulledonrequest

Contact

help@nscc.sg

or

https://servicedesk.nscc.sg

NVIDIAGPUCloud

ToseewhichoptimisedDLframeworksareavailablefromNVIDIAcreateaccounton

/

UsingDockerontheDGX-1

Directaccesstothedockercommandordockergroupisnotpossiblefortechnicalreasons

Utilitiesprovidepre-definedtemplatedDockercommands:

nscc-dockerrunimage

nvidia-docker-u$UID:$GID\

-v/home:/home-v/scratch:/scratch-v/raid:/raid\

--rm-i--shm-size=1g--ulimitmemlock=-1\

--ulimitstack=67108864runimage/bin/sh

nscc-dockerimages

dockerimages

nscc-dockerps

dockerps

Dockerwrapper

$nscc-dockerrun-h

Usage:nscc-dockerrun[--net=host][--ipc=host][--pid=host][-t][-h]IMAGE

--net=host addsdockeroption--net=host

--ipc=host addsdockeroption--ipc=host

--pid=host addsdockeroption--pid=host

-t addsdockeroption-t

-h displaythishelpandexit

--help displaythishelpandexit

--usage displaythishelpandexit

Thefollowingoptionsareaddedtothedockercommandbydefault:

-uUID:GID--group-addGROUP\

–v/home:/home–v/raid:/raid-v/scratch:/scratch\

--rm–i--ulimitmemlock=-1--ulimitstack=67108864

If--ipc=hostisnotspecifiedthenthefollowingoptionisalsoadded:

--shm-size=1g

Singularity

Singularityisanalternativecontainertechnology

Canbeusedasanormaluser

CommonlyusedatHPCsites

Imagesareflatfiles(ordirectories)ratherthanlayers

LatestNGCDockerimagesconvertedtoSingularityimagesand

availablein:

/home/projects/ai/singularity

Examplejobscriptin:

/home/projects/ai/examples/singularity

https://www.sylabs.io/docs/

/docker-compatibility-singularity-hpc/

MultinodeTrainingwithHorovod

HorovodisadistributedtrainingframeworkforTensorFlow,Keras,andPyTorch.

Canbeusedfor:

multi-GPUparallelizationinasinglenode

multi-nodeparallelizationacrossmultiplenodesUsesNCCLandMPI

/uber/horovod

Examplejobscriptformulti-nodeHorovodusing

Singularitytorunacrossmultiplenodes:

/home/projects/ai/examples/horovod

CustomImages(Method1)

NSCC

Admin

UsersendsDockerfile

toNSCCAdmin

NSCCadminperforms"dockerbuild"andsynchronizesimageonallDGXnodes

NSCC

DGX-1

Local

resource

UserlogsintoNSCC

Usercreatesandtests

Dockerfile

Userperforms"nscc-dockerrun"

UsercreatesDockerimagelocallyandsendsDockerfiletoNSCCadmin

CustomImages(Method2)

DockerHub

Userperforms

"dockerpush"

NSCCadminperforms

"dockerpull"onallDGX

Local

resource

UserrequestsNSCCtopullimage

UsercreatesDockerfile

Userperforms"dockerbuild"

NSCC

Userperforms"nscc-dockerrun"

UsercreatesDockerimagelocallyandpushesimagetoDockerHub

Custompythonpackages

#“pipinstall”failsduetopermissionserror#“pipinstall--user”installsinto~/.local

# Thisisnotbestpracticeasitisexternaltocontainer# Itcanalsocauseunexpectedconflicts

#UsePYTHONUSERBASEtoinstallpackagesinsidecontainer

nscc-dockerrunnvcr.io/nvidia/tensorflow:latest<<EOFmkdir/workspace/.local

exportPYTHONUSERBASE=/workspace/.local

pipinstall--userscikit-learn

EOF

#Packagesinstalledwillbewipedoutwhencontainerstops#Forpermanentsolutionbuildacustomimage

Custompythonpackages(virtualenv)

#Installintoavirtualenv(notinstalledindefaultimage)nscc-dockerrunnscc/local/tensorflow:latest<<EOFvirtualenv$HOME/mypthon

.$HOME/mypython/bin/activate

pipinstallscikit-learn

EOF

#virtualenvisinhomedirectorysopersistsaftercontainerstops

#Thereforevirtualenvcanbereused

#Notbestpracticeasitaffectsportabilityandreplicability

nscc-dockerrunnscc/local/tensorflow:latest<<EOF

.$HOME/mypython/bin/activate

pythonscript.pyEOF

sshmiscellany

#ProxyCommandcanmakea2hopsshconnectionappeardirect#Onlocalmachinedo:

cat<<EOF>>.ssh/config

hostdgx410?

ProxyCommandsshaspire.nscc.sgnc%h%p

usermyusernamehostaspire.nscc.sguser