Pegasus - SciTech · PDF fileHTCondor scheduler/broker • Pegasus maps workflows to...
12
Transcript of Pegasus - SciTech · PDF fileHTCondor scheduler/broker • Pegasus maps workflows to...
Key Pegasus Concepts
PegasusWMS==Pegasusplanner(mapper)+DAGManworkflowengine+HTCondorscheduler/broker
• Pegasusmapsworkflowstoinfrastructure• DAGManmanagesdependenciesandreliability• HTCondorisusedasabrokertointerfacewithdifferentschedulers
WorkflowsareDAGs(orhierarchicalDAGs)
• Nodes:jobs,edges:dependencies• Nowhileloops,nocondiPonalbranches
PlanningoccursaheadofexecuPon
• (Excepthierarchicalworkflows)Planningconvertsanabstractworkflowintoaconcrete,executableworkflow
• Plannerislikeacompiler
Pegasus h"ps://pegasus.isi.edu 2
Pegasus h"ps://pegasus.isi.edu 3
cleanup jobRemovesunuseddata
stage-in job
stage-out job
registration job
Transferstheworkflowinputdata
Transferstheworkflowoutputdata
Registerstheworkflowoutputdata
clustered jobGroupssmalljobstogethertoimproveperformance
DAG directed-acyclic graphs
DAX DAG in XML
Pegasus h"ps://pegasus.isi.edu 4
What about data reuse?
data already�available
JobswhichoutputdataisalreadyavailableareprunedfromtheDAG
data reuseworkflow�reduction
data also�available
data reuse
Data Staging Configurations• CondorI/O(HTCondorpools,OSG,…)
• Workernodesdonotshareafilesystem• Dataispulledfrom/pushedtothesubmithostviaHTCondorfiletransfers• Stagingsiteisthesubmithost
• Non-sharedFileSystem(clouds,OSG,…)• Workernodesdonotshareafilesystem• Dataispulled/pushedfromastagingsite,possiblynotco-locatedwiththecomputaPon
• SharedFileSystem(HPCsites,XSEDE,Campusclusters,…)• I/Oisdirectlyagainstthesharedfilesystem
pegasus-transfer• Pegasus’internaldatatransfertoolwithsupportforanumberofdifferentprotocols• DirectorycreaPon,fileremoval
• Ifprotocolsupports,usedforcleanup
• Twostagetransfers• e.g.GridFTPtoS3=GridFTPtolocalfile,localfiletoS3
• Paralleltransfers• AutomaPcretries• CredenPalmanagement
• UsestheappropriatecredenPalforeachsiteandeachprotocol(even3rdpartytransfers)
HTTPSCPGridFTPGlobusOnlineiRodsAmazonS3GoogleStorageSRMFDTstashcpcpln-s
pegasus-transfer• Pegasus’internaldatatransfertool• Supportsmanydifferentprotocols• DirectorycreaPon,fileremoval
• Ifprotocolsupports,usedforcleanup• Twostagetransfers
• e.g.GridFTPtoS3=GridFTPtolocalfile,localfiletoS3• Paralleltransfers• AutomaPcretries• Checkpointandrestarttransfers• CredenPalmanagement
• UsestheappropriatecredenPalforeachsiteandeachprotocol(even3rdpartytransfers)
Protocols- HTTP- SCP- GridFTP- iRods- AmazonS3- GoogleStorage- SRM- FDT- stashcp- cp- ln-s
Pegasus h"ps://pegasus.isi.edu
$OSG_SQUID_LOCATION / http_proxy
• $OSG_SQUID_LOCATIONissetbymanysites• Butdoesitwork?• DoesitworkfortheparPcularhfpsourcetheuserneeds?
• pegasus-transferwilluse$OSG_SQUID_LOCATIONif• hfp_proxyisnotspecifiedbytheuser• forthefirsttransferafempt
AdvancedLIGO–LaserInterferometerGravita>onalWave
Observatory
Pegasus h"ps://pegasus.isi.edu 9
Replica catalog – multiple sources
pegasus.conf
# Add Replica selection options so that it will try URLs first, then # XrootD for OSG, then gridftp, then anything else pegasus.selector.replica=Regex pegasus.selector.replica.regex.rank.1=file:///cvmfs/.* pegasus.selector.replica.regex.rank.2=file://.* pegasus.selector.replica.regex.rank.3=root://.* pegasus.selector.replica.regex.rank.4=gridftp://.* pegasus.selector.replica.regex.rank.5=.\*
# This is the replica catalog. It lists information about each of the # input files used by the workflow. You can use this to specify locations # to input files present on external servers. # The format is: # LFN PFN site="SITE" f.a file:///cvmfs/oasis.opensciencegrid.org/diamond/input/f.a site=“cvmfs" f.a file:///local-storage/diamond/input/f.a site=“prestaged“ f.a gridftp://storage.mysite/edu/examples/diamond/input/f.a site=“storage"
Replica Catalog
pega
sus-
kick
star
t
h"ps://pegasus.isi.edu 11Pegasus
Provenance data can be summarized
(pegasus-statistics) or used for
debugging (pegasus-analyzer)
------------------------------------------------------------------------------ Type Succeeded Failed Incomplete Total Retries Total+Retries Tasks 100000 0 0 100000 543 100543 Jobs 20206 0 0 20206 604 20810 Sub-Workflows 0 0 0 0 0 0 ------------------------------------------------------------------------------ Workflow wall time : 19 hrs, 37 mins Cumulative job wall time : 1 year, 5 days Cumulative job wall time as seen from submit side : 1 year, 27 days Cumulative job badput wall time : 2 hrs, 42 mins Cumulative job badput wall time as seen from submit side : 2 days, 2 hrs
$ pegasus-analyzer pegasus/examples/split/run0001 pegasus-analyzer: initializing... ****************************Summary Total jobs : 7 (100.00%) # jobs succeeded : 7 (100.00%) # jobs failed : 0 (0.00%) # jobs unsubmitted : 0 (0.00%)
Pegasus Automate,recover,anddebugscienPficcomputaPons.
Get Started
PegasusWebsitehfp://pegasus.isi.edu
HipChat
est. 2001
