G4HPC Planning 1202012

We had our first Geant4 FWP planning meeting on 1/19/2012. These are the notes from the whiteboard. When the new redmine site/repo is available, this page should be moved to that location.

general things that need to be addressed

Development environment

  • Applications? - simplified calorimeter, CMSEXP
  • Geant4 base version? - Geant4-9.5 installed as UPS product
  • Compiler? - 4.6.x
  • Performance tools? - CodeAnalyst, CallGrind, FAST, (perhaps Openspeedshop and TAU)
  • Repository? - yes, in redmine, started with snapshot of the above Geant4 code
  • Tools for parallel work? - the standard set of OpenMP, TBB, CUDA, OpenCL, (perhaps Charm++ and a few others of its type)
  • UPS-lite use? - yes, hierarchy of products needs to be spelled out and implemented

Analysis task

  • analysis and restructuring document
  • break out of G4 components that we will be studying
  • thing to be measured
    • memory use for geometry
    • types of queries made to geometry in a realistic setting
    • pattern of access or use of the geometry
  • program traces for validation (particle trajectories, function call parameters, etc.)
  • configuration of Geant4 applications (to study geometry)
  • what should the interactions with geometry look like? (Philippe says that some work on this is underway at CERN - APIs, functionality, etc.)


For Jan 31

  • development and runtime environment
  • applications configured, installed, easy to run
  • verify everything is working (run applications and check output)

For Feb 29

  • rerun Philippe's performance benchmark runs
  • resource use of geometry and propagation components
  • generate G4 sample "input file" for test runs, consisting of primaries and secondaries from a run of CMSEXP, keeping track of path length.
  • run this "input file" through the applications with no physics processes on, and write out the trajectories. This gives up a large set of starting points and answers to begin testing alternative organizations of geometry / magnetic field calculations.
  • start design of standalone application to propagate particles
  • design for magnetic field handling