ALICE OFFLINE :ORGANIZATION

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ALICE OFFLINE ORGANIZATION

• A user point of view
• Yves Schutz, SUBATECH, France

(PHOS biased)
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Toward AliRoot

• A single framework for all computing activities
  in ALICE
• Simulation Online Offline (ReconstructionAnal
  ysis)
• Be friendly to the user (not necessarely user
  friendly !)
• PAW was a success

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Toward AliRoot

• The framework must be adapted to
• The particularities of the experiment
• Large events gt 80 Mb
• Many events gt 2(2) Pb/year
• Huge data flow gt 1 Gb/s

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Toward AliRoot

• The framework must be adapted to
• Any (most) user (about 900)
• Rapidly usable (even if unstable)
• Available on all major platforms
• Low learning threshold
• Looks like a-postiori design criteria for Root

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• All OO C
• The unique framework is AliRoot (same language
  for script and implementation)
• Fortran is tolerated (GEANT3.21 wrapped)
• Open source (user potential developper)

An often disputed (at CERN) choice but it works !
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Organisation
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Alice User
Talks to root Through a macro
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Alice User
Talks to root Through a macro
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Alice User
Talks to root Through a macro
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Alice User
Talks to root Through a macro
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Alice User
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Simulator
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Reconstructioner
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Developers and users

• About 900 potential users
• About 50 developers scattered arround the world
• Steering group at CERN ( 5 persons )
• 1-2 developper-librarian/detector
• About 5 (regularoccasional) developpers/detector

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To stay within the frame(work)

• The offline board
• The steering group
• The librarians
• Meets every week (micro), 6 weeks (macro)
• Users training
• 4 one-week meetings/year
• Users developpers
• Presentations classes

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but not enough

• ALICE defined Coding Conventions
• Strictly enforced (blame/shame)
• Automatic tool
• Syntax
• Naming
• Style
• make check
• .viol

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Maintenance

• CERN based CVS Repository
• Librarian have exclusive commit rights
• Developpers are automatically informed by e-mail
• HEAD must compile, not necessarely bug free
• Every 2 weeks a release (3.02) bug free, usable
  by any user

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Documentation

• Root builds html documentation (to be improved)
• Root does reverse engeenering (uml look alike)
• Every detector responsible for its own
  documentation
• Collected on a single WWW page

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http//AliSoft.cern.ch/offline
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Documentation

• Root builds html documentation (to be improved)
• Root does reverse engeenering (uml look alike)
• Every detector responsible for its own
  documentation
• Collected on a single WWW page