Using Ganga to submit jobs to the Panda backend on lxplus

References:

Full Ganga Atlas Tutorial

Data preparation reprocessing - using Ganga

1. In a clean lxplus afs shell, setup Ganga.

  source /afs/cern.ch/sw/ganga/install/etc/setup-atlas.sh

2. Setup the athena release.

NOTE: To set up for any release one must be familar with using CMT (bootstrap procedures and requirement files) - see here for more information. In this example (for reprocessing see the reference page above for the necessary release) once the requirements file is set up and a release directory in your test area is created then try:

  source ~/cmthome/setup.sh -tag=14.5.2.6,32,AtlasProduction

3. Setup any checked out packages you use in your code.

For this example check out (and compile) the UserAnalysis package as in the "HelloWorld"example here or here.

  cd $TESTAREA/14.5.2.6/PhysicsAnalysis/AnalysisCommon/UserAnalysis/cmt
  source setup.sh

NOTE: For demonstration purposes (to show that this setup does indeed pull in the code changes made to a checked out package) - I have appended to a comment in AnalysisSkeleton.cxx (i.e I changed "No AOD MC truth particle container found in TDS" to "No AOD MC truth particle container found in TDS - This comment changed by Tom")

4. Go to run directory and start ganga (once the code is compiled).NOTE ganga picks up your grid cert/key from your .globus directory on lxplus - if you have not created these files please follow the instructions here under the preparing the certificate section. Also you must create a file called 'vomses' in a new directory called .glite (again note the '.') and enter this line for the ATLAS VO - "atlas" "voms.cern.ch" "15001" "/C=CH/O=CERN/OU=GRID/CN=host/voms.cern.ch" "atlas" into this file.

   cd ../run
   ganga

5. Before you prepare/run your Ganga JO you must prepare the Athena JO it points to.For this you can use the top job options copied from your UserAnalysis packages share directory.

cp ../share/AnalysisSkeleton_topOptions.py .

BUT to prepare your code for running on the Grid there are some changes needed for this Athena JO - please add these lines:

______________________________________________________________________________

include("RecExCommission/RecExCommissionFlags_jobOptions.py" )
ATLASCosmicFlags.useLocalCOOL  = True
# setup DBReplicaSvc to choose closest Oracle replica, configurables style
from AthenaCommon.AppMgr import ServiceMgr
from PoolSvc.PoolSvcConf import PoolSvc
ServiceMgr+=PoolSvc(SortReplicas=True)
from DBReplicaSvc.DBReplicaSvcConf import DBReplicaSvc
ServiceMgr+=DBReplicaSvc(UseCOOLSQLite=False) 

_____________________________________________________________________________

Also remember to remove (or comment out) the input data line and if you are running a reprocessing job change the geometry tag and the conditions DB tag to match those used in the reprocessing cycle (see details for each reprocessing campaign on this page here. For example:

globalflags.ConditionsTag.set_Value_and_Lock('COMCOND-REPC-002-13')

6. Execute your Ganga job script while Ganga is running (where an example of what the 'pandaBackend_test.py' would look like is below in other words have this file in your run directory) and type:

    execfile('pandaBackend_test.py') 

or simply from the command line run ganga with the name of the Ganga JO appended:

    ganga pandaBackend_test.py

6. You can monitor your job's progress by typing jobs inside Ganga or, if you submitted to the Panda backend by http://panda.cern.ch:25880/server/pandamon/query.

7. Once your job has finished you can copy the output data using the dq2 tools.

          
source /afs/cern.ch/atlas/offline/external/GRID/ddm/DQ2Clients/setup.sh
   dq2-get "your_dataset_name"

Where "your_dataset_name" is given to you by Ganga once the job completes. Also once the job completes Panda in particular sends you an email like this. In the email if you click on the 'PandaMonURL' link - in my case for job id 81.Then click on any of the sub-job pandaID's for example ' 1026613035' then scroll down to the link 'Find and view log files' - you can look at the Ganga log for your subjob which is named 'athena_stdout.txt' (only look at 'athena_stderr.txt if your job does not complete). I can then find that"No AOD MC truth particle container found in TDS - This comment changed by Tom" appears in this log.

The Ganga JO 'pandaBackend_test.py' could look like this (without line numbers):

1    j = Job()
2    j.application = Athena()
3    j.application.atlas_dbrelease = 'ddo.000001.Atlas.Ideal.DBRelease.v06060101:DBRelease-6.6.1.1.tar.gz'
4    j.application.option_file = 'AnalysisSkeleton_topOptions.py'
5    j.application.athena_compile = False
6    j.application.prepare()
7    j.inputdata = DQ2Dataset()
8    j.inputdata.dataset = "data08_cos.00092051.physics_IDCosmic.recon.ESD.o4_r653/"
9    j.outputdata = DQ2OutputDataset()
10   j.backend = Panda()
11   j.splitter = DQ2JobSplitter()
12   j.splitter.numsubjobs = 20
13   j.submit()

NOTE: Line 3 is an example of overriding a database release to match the one needed to read ESD/DPD. In the case of the spring cosmic reprocessing,the DB release is 6.6.1.1. If the database releases don't match the jobs fail on the Grid ( remove this line if it is not necessary). Line 4 corresponds to your Athena jobOptions. Line 5 is set to False because we have already compiled the packages locally if you want your job to compile your checked out code before submitting then simply change this to True Line 6 tells Ganga to tar your user area and send it with the job. Line 10 specifies the backend to which you are sending your job. There are three options: LCG, Panda and NorduGrid. In the example above Panda was chosen because the data existed only in BNLPANDA, a site in the US cloud. Line 12 corresponds to the number of subjobs you want to split your job into. Finally in Line 13 you submit your job