| 1 | $Id: NEW_APP_README,v 1.2 2002/03/09 10:15:01 cooperma Exp $
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| 2 | ------------------------------------------------------------------------------
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| 3 | This file and NEW_APP_INSTALL describe important information if you are
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| 4 | planning to create a new parallel Geant4 application, similarly
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| 5 | to the examples ParN02 and ParN04.
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| 6 | This package implements event-level parallelism for Geant4
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| 7 | using the free TOP-C distribution. (TOP-C = Task Oriented Parallel C/C++)
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| 8 |
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| 9 | To parallelize an existing sequential Geant4 application, read NEW_APP_INSTALL.
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| 10 |
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| 11 | The design goals are:
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| 12 | 1. No modification of the Geant4 kernel libraries.
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| 13 | 2. Application sessions should be efficient and reproducible
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| 14 | (independently of the number of slave processes and the
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| 15 | order in which they are called by TOP-C)
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| 16 | 3. Setting deterministic random seeds on each slave
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| 17 | [ This code assumes that each slave will initialize its random state
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| 18 | based on either the event number or a random seed selected
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| 19 | on the master.]
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| 20 |
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| 21 | This assumes that you have already installed CLHEP, Geant4, and TOP-C
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| 22 | TOP-C can be downloaded via its home page:
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| 23 | http://www.ccs.neu.edu/home/gene/topc.html
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| 24 |
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| 25 | Other qualifications are:
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| 26 | 1. It has only been tested under Linux, although it should be
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| 27 | portable to any other UNIX supported by Geant4.
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| 28 | 2. Since Geant4 does not currently support a uniform format for
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| 29 | tracker hits, calorimeter hits, etc., on new applications,
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| 30 | you may have to write marshalling code for your hits, based
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| 31 | on the examples in ParN02 and ParN04.
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| 32 | 3. This should support histograms as long as AnalysisManager::Step() is
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| 33 | is trivial. However, I have not had the opportunity
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| 34 | for careful testing. Please write to gene@ccs.neu.edu if you
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| 35 | are including histograms, and especially if you define
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| 36 | AnalysisManager::Step().
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| 37 | 4. Currently, this distribution does not support:
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| 38 | trajectory stores, n-tuples, track parallelism,
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| 39 | interactive input commands (no macrofile)
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| 40 | I plan to add those features according to demand.
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| 41 | Probably: a. allowing interactive input
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| 42 | b. track-level parallelism
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| 43 | c. other (trajectory store, PostponeOneEvent(), ...)
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| 44 |
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| 45 | Some design assumptions in this ParGeant4 implementation:
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| 46 | 1. A collectionName for a G4HitsCollection uniquely identifies the
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| 47 | G4HitsCollection within a G4HCofThisEvent.
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