Job Services and Data Services Giuseppe La Rocca INFN Catania

1. EGEE Tutorial Turin - ITALY 18 – 19 January 2005 www.eu-egee.org Job Services and Data ServicesGiuseppe La RoccaINFN Catania EGEE is a project funded by the European Union under contract IST-2003-508833

2. Overview • Files on the RLS - Name Convention • Job Description Language - Overview • Relevant attributes • JDL Examples • Job without Data Requirements • Job with Output Data • Job with Input and Output Data • Other examples using the lcg-* commands • Bibliography • Summary and Conclusions

3. Physical File SURL 1 Logical File Name 1 . . . . GUID Physical File SURL n Logical File Name n Files on the RLS - Name Convention • Globally Unique Identifier (GUID) • A non-human-readable unique identifier for a file, e.g. “guid:f81d4fae-7dec-11d0-a765-00a0c91e6bf6” • Site URL (SURL)(or Physical/Site File Name (PFN/SFN)) • The location of the actual file on a storage system, e.g. “sfn://lxshare0209.cern.ch/data/alice/ntuples.dat” • Logical File Name (LFN) • An alias created by a user to refer to some file, e.g. “lfn:cms/track1” • Transport URL (TURL) • A temporary URL which can be used to access a particular data file contained in a Storage Element e.g. “gsiftp://lxshare0209.cern.ch//data/alice/ntuples.dat”

4. Job Description Language (1) • In LCG-2 Job Description Language (JDL) are used to describe jobs for execution on Grid. • The JDL adopted within the LCG-2 middleware is based upon Condor’s CLASSified Advertisement language (ClassAd). • A ClassAd is a record-like structure composed of a finite number of attribute separated by semi-colon (;) • A ClassAd is highly flexible and can be used to represent arbitrary services The JDL is used in LCG-2 to specify the desired job characteristics and constrains, which are used in by match-making process to select the resources that the job will use.

5. Job Description Language (2) • The JDL syntax consists on statements like: Attribute = value; • Comments must be preceded by a sharp character ( # ) or have to follow the C++ syntax WARING: The JDL is sensitive to blank characters and tabs. No blank characters or tabs should follow the semicolon at the end of a line.

6. Job Description Language (3) • In a JDL, some attributes are mandatory while others are optional. • A essential JDL is the following: Executable = “test.sh”; StdOutput = “std.out”; StdError = “std.err”; InputSandbox = {“test.sh”}; OutputSandbox = {“std.out”,”std.err”}; • If needed, arguments to the executable can be passed: Arguments = “Hello World!”;

7. Job Description Language (4) • If the arguments contains quoted strings, the quotes must be escaped with a backslash e.g. Arguments = “\”Hello World!\“ 10”; • Special characters such as &, |, >, < are only allowed if specified inside a quoted string or preceded by triple \ (e.g. Arguments = "-f file1\\\&file2";)

8. The supported attributes are grouped in two categories: Job Attributes Define the job itself Resources Taken into account by the RB for carrying out the matchmaking algorithm (to choose the “best” resource where to submit the job) Computing Resource Used to build expressions of Requirements and/or Rank attributes by the user Have to be prefixed with “other.” Data and Storage resources Input data to process, SE where to store output data, protocols spoken by application when accessing SEs Job Description Language (5)

9. JDL: Relevant Attributes (1) JobType(optional) Normal (simple, sequential job), Interactive, MPICH, Checkpointable, Partitionable Or combination of them Checkpointable, Interactive Checkpointable, MPI E.g. JobType = “Interactive”; JobType = {“Interactive”,”Checkpointable”};

10. JDL: Relevant Attributes (2) • Type(mandatory, default “Job”) • This is a representing the type of the request described by the JDL. • Possible values are: • Job • DAG • Reservation • Co-allocation E.g. Type = “Job”;

11. JDL: Relevant Attributes (3) • Executable (mandatory) • This is a string representing the executable/command name. • The user can specify an executable that lies already on the remote CE • Executable = {“/opt/EGEODE/GCT/egeode.sh”}; • The user can provide a local executable name, which will be staged from the UI to the WN. Executable = {“egeode.sh”}; InputSandbox = {“/home/larocca/egeode/ egeode.sh”};

12. JDL: Relevant Attributes (4) • Arguments (optional) This is a string containing all the job command line arguments. E.g.: If your executable sum has to be started as: $ sum N1 N2 –out result.out Executable = “sum”; Arguments = “N1 N2 –out result.out”;

13. JDL: Relevant Attributes (5) • Environment (optional) • List of environment settings needed by the job to run properly E.g. Environment = {“JAVABIN=/usr/local/java”}; • InputSandbox(optional) • List of files on the UI local disk needed by the job for running • The listed files will automatically staged to the remote resource E.g. InputSandbox ={“myscript.sh”,”/tmp/cc,sh”};

14. JDL: Relevant Attributes (6) • OutputSandbox(optional) • List of files, generated by the job, which have to be retrieved E.g. OutputSandbox ={ “std.out”, ”std.err”, “image.png”}; • VirtualOrganisation(optional) • This is a string representing the name of the VO the submitting user is currently working for. E.g. VirtualOrganisation =“gilda”;

15. JDL: Relevant Attributes (7) • Requirements(optional) • Job requirements on computing resources • Specified using attributes of resources published in the Information Service • If not specified, default value defined in UI configuration file is considered Default. Requirements = other.GlueCEStateStatus == "Production“;

16. JDL: Relevant Attributes (8) • Rank (optional) • Floating-point expression used to ranks CEs that have already met the Requirements expression. • The Rank expression can contain attributes that describe the CE in the Information System (IS). • The evaluation of the rank expression is performed by the Resource Broker (RB) during the match-making phase. • A higher numeric value equals a better rank. • If not specified, default value defined in the UI configuration file is considered Default: Rank = - other.GlueCEStateFreeCPUs;

17. JDL: Relevant Attributes (9) • InputData (optional) • This is a string or a list of strings representing the Logical File Name (LFN) or Grid Unique Identifier (GUID) needed by the job as input. • The list is used by the RB to find the CE from which the specified files can be better accessed and schedules the job to run there. InputData = {“lfn:cmstestfile”, “guid:135b7b23-4a6a-11d7-87e7-9d101f8c8b70”};

18. JDL: Relevant Attributes (10) • DataAccessProtocol (mandatory if InputData has been specified) • The protocol or the list of protocols which the application is able to “speak” with for accessing files listed in InputData on a given SE. • Supported protocols in LCG-2 are currently gridftp, file and rfio. DataAccessProtocol = {“file”,“gridftp”,“rfio”};

19. JDL: Relevant Attributes (11) • OutputSE (optional) • This string representing the URI of the Storage Element (SE) where the user wants to store the output data. • This attribute is used by the Resource Broker to find a CE being “close” to this SE and schedule the job there. OutputSE = “grid009.ct.infn.it”;

20. JDL: Relevant Attributes (12) • OutputData (optional) • This attribute allows the user to ask for the automatic upload and registration of datasets produced by the job on the Worker Node (WN). • This attribute contains the following three attributes: • OutputFile • StorageElement • LogicalFileName

21. JDL: Relevant Attributes (13) • OutputFile (mandatory if OutputData has been specified) • This is a string attribute representing the name of the output file, generated by the job on the WN, which has to be automatically uploaded and registered by the WMS. • StorageElement (optional) • This is a string representing the URI of the Storage Element where the output file specified in the OutputFile has to be uploaded by the WMS. • LogicalFileName (optional) • This is a string representing the LFN the user wants to associate to the output file when registering it to the Replica Catalogue.

22. JDL: Relevant Attributes (14) OutputData = { [ OutputFile = “dataset1.out”; LogicalFileName = “lfn:test-result1”; ], [ OutputFile = “dataset2.out”; LogicalFileName = “lfn:test-result2”; StorageElement = “grid009.ct.infn.it”; ], [ OutputFile = “dataset3.out”; ] };

23. Examples JDL Without Data Requirements

24. Job Without Data Requirements(1) [ Type = “job”; JobType = “Normal”; Executable = "script.sh"; Arguments = “Giuseppe”; StdOutput = “sim.out”; StdError = “sim.err”; InputSandbox = {"script.sh"}; OutputSandbox = {“sim.err”,“sim.out”};

25. Job Without Data Requirements(2) # A site with more than 4 CPU is required. Requirements=(other.GlueCEInfoTotalCPUs>4); # If more than one resource matches, the resource with the largest # number of CPU is chosen. Rank = (other.GlueCEStateFreeCPUs); ]

26. script.sh #!/bin/sh /bin/echo Hello $1 and Welcome to the EGEE Tutorial!

27. Examples JDL With Output Data

28. Job with Output Data (1) [ Type = “job”; JobType = “Normal”; Executable = “scriptOutput.sh"; Arguments = “Giuseppe”; VirtualOrganisation = “gilda”; StdOutput = “sim.out”; StdError = “sim.err”; InputSandbox = {"scriptOutput.sh"};

29. Job with Output Data (2) OutputSandbox = {“sim.err”, “sim.out”}; OutputData = { [ Outputfile = “TorinoXX.out”; LogicalName = “lfn:TorinoXX.out”; StorageElement = “grid009.ct.infn.it”; ]}; Requirements=(other.GlueCEInfoTotalCPUs>4); Rank=(other.GlueCEStateFreeCPUs); RetryCount = 0; ]

30. scriptOutput.sh #!/bin/sh /bin/echo Hello $1 and Welcome to the EGEE Tutorial! > TorinoXX.out

31. Examples JDL With Input Data

32. Job with Input Data (1) [ Type = “job”; JobType = “Normal”; Executable = “scriptInput.sh"; Arguments = “Francesco”; VirtualOrganisation = “gilda”; StdOutput = “std.out”; StdError = “std.err”;

33. Job with Input Data (2) InputSandbox = {“scriptInput.sh"}; OutputSandbox = {“std.err”, “std.out”}; InputData = “lfn:myoutdata.1”; DataAccessProtocol = {“gridftp”,”rfio”}; Requirements=(other.GlueCEInfoTotalCPUs>4); Rank=(other.GlueCEStateFreeCPUs); RetryCount = 0; ]

34. scriptInput.sh #!/bin/sh lcg-cp –vo gilda lfn:myoutdata.1 file:`pwd`/dataset1.out echo “Before updating..” cat dataset1.out #Adding new entry on the dataset1.out file. /bin/echo Hello $1 and Welcome to the EGEE Tutorial! >> dataset1.out echo “After updating..” cat dataset1.out

35. Examples Interact with the RLS using the lcg-* commands

36. StoreData.jdl Type="Job"; JobType="Normal"; Executable="StoreData.sh"; Arguments="myfile myfile grid009.ct.infn.it"; VirtualOrganisation="gilda"; StdOutput="std.out"; StdError="std.err"; InputSandbox={"StoreData.sh","myfile"}; OutputSandbox={"std.out","std.err"}; Requirements=(other.GlueCEInfoTotalCPUs > 4); Rank=other.GlueCEStateFreeCPUs;

37. StoreData.sh (1) #!/bin/sh ARGS=3 ERROR_BADARGS=10 # Bad arguments error ERROR_FILE=20 # File to copy on RLS doesn't exist ERROR_STORAGE=30 # Storage Element doesn't exist in this Catalog. # Check for proper no. of command line args. if [ $# -ne $ARGS ] then echo "Usage: `basename $0` [text-file2copy] [lfn-file2copy] [se-name]" exit $ERROR_BADARGS

38. StoreData.sh (2) else # Setting the variables for the script. FILE2COPY=$1 LFN2COPY=$2 SENAME=$3 fi # Check if the ${FILE2COPY} exists on the path. if [ ! -e `pwd`/${FILE2COPY} ] then echo "Error: `basename $0.` ${FILE2COPY} does not exist on the path." exit ${ERROR_FILE} fi

39. StoreData.sh (3) # Checking if the SENAME is a good SE where to store data. lcg-infosites --vo gilda closeSE | grep ${SENAME} if [ $? -eq 0 ] then # Uploading the copy on the RLS. lcg-cr --vo gilda -d ${SENAME} -l ${LFN2COPY} file:`pwd`/${FILE2COPY} else echo Sorry, but you have to specific a good Storage Element. exit $ERROR_STORAGE fi

40. UpdateData.jdl Type="Job"; JobType="Normal"; Executable=“UpdateData.sh"; Arguments="myfile Julia grid009.ct.infn.it"; VirtualOrganisation="gilda"; StdOutput="std.out"; StdError="std.err"; InputSandbox={“UpdateData.sh"}; OutputSandbox={"std.out","std.err"}; Requirements=(other.GlueCEInfoTotalCPUs > 4); Rank=other.GlueCEStateFreeCPUs;

41. UpdateData.sh (1) #!/bin/sh ARGS=3 ERROR_BADARGS=10 # Bad arguments error. ERROR_BADLFN=20 # LFN doesn't exist on the RLS. ERROR_BADSTORAGE=30 # Storage Element doesn't exist in this Catalog. # Check for proper no. of command line args. if [ $# -ne $ARGS ] then echo "Usage: `basename $0` [lfn-file2copy] [argument] [se-name]" exit ${ERROR_BADARGS} else # Setting the arguments for the script. LFN2RETRIEVE=$1 ARGUMENT=$2 SENAME=$3 fi

42. UpdateData.sh (2) # Check if the ${LFN2RETRIEVE} exists on the RLS. lcg-lr --vo gilda lfn:${LFN2RETRIEVE} if [ $? -eq 1 ] then echo "Sorry, but the LFN that you have specified does not exists on the RLS". exit ${ERROR_BADLFN} else # Retrieve the file from the catalog... lcg-cp --vo gilda lfn:${LFN2RETRIEVE} file:`pwd`/myfile # ...adding new data to myfile. echo Hello ${ARGUMENT} and Welcome to the EGEE Tutorial!! >> `pwd`/myfile fi # Checking if the SENAME is a good SE where to store data. lcg-infosites --vo gilda closeSE | grep ${SENAME}

43. UpdateData.sh (3) if [ $? -eq 1 ] then echo Sorry, but you have to specific a good Storage Element. exit ${ERROR_STORAGE} else # Setting the variables for the new copy. FILE2COPY=`pwd`/myfile LFN2COPY=${LFN2RETRIEVE} # Removing the old copy form the RLS... lcg-del --vo gilda -a lfn:${LFN2COPY} # ... and staging the new data on the RLS. lcg-cr --vo gilda -d ${SENAME} -l ${LFN2COPY} file:${FILE2COPY} echo "Your data has been correctly uploaded to the RLS.” echo “Have a nice day!!" fi

44. JDL Attributes http://server11.infn.it/workload-grid/docs/DataGrid-01-TEN-0142-0_2.pdf • LCG-2 User Guide Manual Series http://egee-na4.ct.infn.it/documentation/LCG-2-Userguide.pdf • EDG Tutorial http://www.dutchgrid.nl/DataGrid/introduction/edg-tutorial-handout.pdf • EDG Users’ Guide http://marianne.in2p3.fr/datagrid/documentation/EDG-User-Guide-2.0.pdf

45. Summary & Conclusions We explained the main attributes to create and submit basic JDL on the GRID. Jobs which interacts with the RLS through the JDL Jobs which interacts with the RLS using the lcg-* commands.

46. Questions…