Garfield on the Grid

Garfield is a computer program for the detailed simulation of two- and three-dimensional drift chambers.

See Garfield homepage.

Background information

• Garfield application runs currently in geant4 VO
• Garfield executable and libraries are installed on-the-fly via the input sandbox.
• The work area on AFS is: /afs/cern.ch/sw/arda/install/Garfield:
  • install: Garfield installation
  • examples: examples and test area for ARDA team
  • user: test area for Garfield users and developers
  • Garfield.ini : ganga configuration file
  • scripts : ganga scripts for Garfield (submit_garfield.py)

The good starting point is /afs/cern.ch/sw/arda/install/Garfield/examples/example1. Copy it to your work area.

Instructions

Setup

• Put Ganga in your path and point it to the correct configuration (see also: http://cern.ch/ganga/install)
  • export PATH=/afs/cern.ch/sw/ganga/install/4.2.11/bin:$PATH
  • export GANGA_CONFIG_PATH=/afs/cern.ch/sw/arda/install/Garfield/Garfield.ini
• Make sure you have the certificate or a proxy for the VO! more info needed
• Login to lxplus

Ganga manual

• tutorial: http://cern.ch/ganga/user/html/GangaIntroduction
• more documentation: http://cern.ch/ganga/user/index.html

Usage example

• this example requires that you have ./generator_ArCO2 in your current working directory
• submit ten jobs to LSF
  • ganga submit_garfield.py ./generator_ArCO2 1 10 LSF
• submit 5 jobs to the Grid with cpu limit >= 10 hours (600 minutes)
  • ganga submit_garfield.py --cputime=600  ./generator_ArCO2 15 20 LCG
• additional files may be specified with --infiles=FILE1,FILE2
• by default the /afs/cern.ch/sw/arda/install/Garfield/scripts/submit_garfield.py is used
• you can use a local copy of this script if you specify a path to it: ganga ./mydir/submit_garfield.py ....

Getting job output

• start ganga and select the job:
  • j=jobs[i]
• the output directory is printed like this:
  • print j.outputdir
• you can list the directory like this:
  • !ls -l $j.outputdir
• you can inspect the files in the outputdir like this:
  • j.peek()
  • j.peek('file') (the output files will most likely be in the tarball)

Atlas MDT Example (Muon Chambers)

This runs a generator with a background.

cd /afs/cern.ch/sw/arda/install/Garfield/examples/examplemdt

ganga submit_garfield.py --infiles=dist_ex.gas,mdt-res.gas ./generator_mdt_bkg 1 10 LSF

*.hist are produced by the jobs, concatenate them into a single file total-mdt-res-bkg.hist

run ./garfield-9

Main: < plotmdt

https://twiki.cern.ch/twiki/bin/view/ArdaGrid/GarfieldGridInstructions

-- JakubMoscicki - 07 Mar 2007