1. ATLAS Software Kaushik De University of Texas At Arlington based on a tutorial by P. Calafiura (LBNL) LHC Computing Workshop, Ankara May 2, 2008

2. References Workbook https://twiki.cern.ch/twiki/bin/view/Atlas/WorkBookAthena Wiki: https://twiki.cern.ch/twiki/bin/view/Atlas/CoreSoftware https://twiki.cern.ch/twiki/bin/view/Atlas/CoreSoftware Glossary: http://cern.ch/wlav/athena/athask/glossary.html http://cern.ch/wlav/athena/athask/glossary.html ATLAS Code LXR indexer: http://alxr.usatlas.bnl.gov/http://alxr.usatlas.bnl.gov/ cvs repository: http://atlas-sw.cern.ch/cgi-bin/viewcvs-atlas.cgi/offline/ http://atlas-sw.cern.ch/cgi-bin/viewcvs-atlas.cgi/offline/ Doxygen summary: http://atlas-computing.web.cern.ch/atlas- computing/links/nightlyDocDirectory/allpackages.html http://atlas-computing.web.cern.ch/atlas- computing/links/nightlyDocDirectory/allpackages.html

3. Platform and Releases ATLAS software certified on linux SLC4 with gcc 3.4.x in 32 bits mode  Also built in native 64 bits and with gcc 4.1  Port to Mac OS long-standing low priority goal  No Windows version planned Regular developer and production releases  14.0.0 next production release, being validated  14.1.0 latest developer, being validated  13.0.40.3 latest production “cache” (bugfix patched release, distributed to Tier Xs)

4. Code Distribution  Each release, and many nightly builds can be installed on your laptop using pacman distribution kits  Mainly geared towards grid production and running existing code  Usable for code development https://uimon.cern.ch/twiki/bin/view/Atlas/WorkBookInstalli ngAtlasSoftware

5. CMT Configuration Management Tool www.cmtsite.org  Used for almost everything  Build releases  Setup work environment  Compile and install your code, jo files,...  Generate documentation  Create distribution kits https://twiki.cern.ch/twiki/bin/view/Atlas/CMTInAtlas

6. AtlasLogin Standard environment setup CMT package takes care of setting up core cmt environment ● $CMT..CONFIG,..PATH,..PROJECTPATH ● Differ per release, and per workspace ● Define lookup for rest of environment setup ● CMT project, part of releases and kit Centrally maintained (lots of work) Reasonably customizable Easy to use! > setup 13.2.0,dbg https://twiki.cern.ch/twiki/bin/view/Atlas/AtlasLogin

7. Important envars (1)  $CMTCONFIG  Determined by platform, compiler, and dbg or opt. Defines library selection and compiler/linker options  $CMTPATH  Search path for finding packages.  $CMTPROJECTPATH  Search path for finding projects  cmt show path  As envars above can change on-the-fly Bootstrap Settings

8. Important envars (2)  $JOBOPTSEARCHPATH  For athena.py to find job options files  $DATAPATH  For PathResolver to find data files  $PATH  For shell to find binaries  $LD_LIBRARY_PATH  For dld.so to find libraries  $PYTHONPATH  For python to find modules Final Settings

9. Athena in a nut shell Athena is based on LHCb's GAUDI

10. Job Options Use python scripts to configure  Global job properties  Verbosity, inputs, outputs, no of evts to process,...  Hierarchy of JobProperties containers jobproperties.CaloCellFlags.doLArCellEmMisCalib()  Detector tasks  Digitize InDet, Reconstruct Pixel, skip LAr,...  https://twiki.cern.ch/twiki/bin/view/Atlas/DetFlags https://twiki.cern.ch/twiki/bin/view/Atlas/DetFlags  Gaudi Components (Algs, Tools, Services)  via Configurables, python classes mirroring C++  Set component properties, see doc, default values https://twiki.cern.ch/twiki/bin/view/Atlas/configurableMigration

11. Selected Top-level Job Options HelloWorld http://alxr.usatlas.bnl.gov/lxr/source/atlas/Control/AthenaExamples/AthExHelloWorld/share/H elloWorldOptions.py http://alxr.usatlas.bnl.gov/lxr/source/atlas/Control/AthenaExamples/AthExHelloWorld/share/H elloWorldOptions.py http://alxr.usatlas.bnl.gov/lxr/source/atlas/Control/AthenaExamples/AthExHelloWorld/share/H elloWorldOptions.py Job Options Examples (more advanced) http://alxr.usatlas.bnl.gov/lxr/source/atlas/Control/AthenaExamples/AthExJobOptions/share/ http://alxr.usatlas.bnl.gov/lxr/source/atlas/Control/AthenaExamples/AthExJobOptions/share/ Digitization (and pileup) http://alxr.usatlas.bnl.gov/lxr/source/atlas/Simulation/Digitization/share/DigitizationRTT_all_pi leup10_perfmon.py http://alxr.usatlas.bnl.gov/lxr/source/atlas/Simulation/Digitization/share/DigitizationRTT_all_pi leup10_perfmon.py http://alxr.usatlas.bnl.gov/lxr/source/atlas/Simulation/Digitization/share/DigitizationRTT_all_pi leup10_perfmon.py RecExCommon (standard offline reco) http://alxr.usatlas.bnl.gov/lxr/source/atlas/Reconstruction/RecExample/RecExCommon/shar e/RecExCommon_topOptions.py RecExCommission (combined cosmic reco) http://alxr.usatlas.bnl.gov/lxr/source/atlas/Reconstruction/RecExample/RecExCommission/share/R ecExCommission_topOptions.py AODtoDPD (primary DPD maker) http://alxr.usatlas.bnl.gov/lxr/source/atlas/PhysicsAnalysis/DPDUtils/share/AODtoDPD.py

12. Job Transformations Python scripts used to run production tasks  More complex than job options scripts  Variable configuration (e.g. Input files)  Validate results, produce report  Flexible framework helps writing them https://twiki.cern.ch/twiki/bin/view/Atlas/AtlasPythonTrf  Many ready to use  Event Generators  G4 simulation, digitization/pileup  Reconstruction