HSF Detector Simulation on GPU Community Meeting

3 May 2022, 15:00 → 6 May 2022, 19:00 Europe/Zurich

Zoom

Live Notes for Questions, Comments, Discussion

Tuesday 3 May

15:00 → 19:00 Workshop Sessions: Session 1

15:00 Introduction

Speaker: Witold Pokorski (CERN)

HSFGPU_intro.pdf

15:10 AdePT project overview, current status and perfomance

Functionality overview:
- project structure, components, library organization
- targeted/achieved functionalities

Implementation overview:
- components internals, basic data structures host/device
- random number handling and reproducibility
- workflow(s), scheduling and event loop implementations
- scoring and data transfers

Performance overview
- Current performance status
- Main bottlenecks discussion

Speakers: Andrei Gheata (CERN), Guilherme Amadio (CERN), Jonas Hahnfeld (CERN), Stephan Hageboeck (CERN), Witold Pokorski (CERN)

AdePT_implementation.pdf

AdePT Performance Overview.pdf

AdePT_project_overview-3.pdf

16:10 Coffee break

16:30 Celeritas project overview, current status and performance

Code overview:
- background and motivation
- codebase overview, including dependencies
- components overview

Performance:
- Metrics
- OLCF Summit results
- Profiling

Speakers: Amanda Lund, Seth Johnson (Oak Ridge National Laboratory), Tom Evans (Oak Ridge National Laboratory)

1a-code-overview.pdf

1b-performance.pdf

17:30 Discussion

Wednesday 4 May

15:00 → 19:00 Workshop Sessions: Session 2

15:00 AdePT geometry and magnetic field

VecGeom overview and experience

Current VecGeom GPU support
- data model on host/device and dependency on CUDA
- model data transfer and initialization on GPU
- geometry optimizations (navigation states, single-precision, BVH)
- navigation and current fundamental problems on GPU
- evolution path for VecGeom GPU support: surface models

Magnetic field handling

Speakers: Andrei Gheata (CERN), Benjamin Morgan (University of Warwick (GB)), Guilherme Amadio (CERN), John Apostolakis (CERN), Stephan Hageboeck (CERN)

2.1-VecGeom Library.pdf

2.2-Adept-Propagating-in-Magnetic-Field.pdf

2.2-Adept-Propagating-in-Magnetic-Field.pptx

2.3_VecgeomBuildStatus.pdf

2.4-VecGeom_GPU_plans.pdf

VecGeom Library (Google Slides)

16:00 Coffee break

16:20 Celeritas geometry and magnetic field

Celeritas/VecGeom integration

ORANGE: Oak Ridge geometry engine
- background
- features, status, goals
- code examples

Magnetic field in Celeritas
- background and methods
- standalone field performance

Speakers: Guilherme Lima (FermiLab (US)), Seth Johnson (Oak Ridge National Laboratory), Soon Yung Jun (Fermi National Accelerator Lab. (US))

2a-vecgeom.pdf

2b-orange.pdf

2c-magnetic-field.pdf

17:20 Discussion

Thursday 5 May

15:00 → 19:00 Workshop Sessions: Session 3

15:00 AdePT physics

• general design and interface with transport
• available processes
• physics validation
• GPU vs CPU performance and issues

Speakers: Jonas Hahnfeld (CERN), Mihaly Novak (CERN)

3.1_physics1_G4HepEm_HSF_GPU_2022_May_MNovak.pdf

AdePT_physics.pdf

16:00 Coffee break

16:20 Celeritas physics

Physics interface
- transport loop and control flow
- physics kernels

Physics "perspectives"
- available processes
- data management and components

Physics verification/validation
- geant4 helper app
- current test problems

Speakers: Seth Johnson (Oak Ridge National Laboratory), Soon Yung Jun (Fermi National Accelerator Lab. (US)), Stefano Tognini

3a-physics-interface.pdf

3b-physics-perspectives.pdf

3c-physics-validation.pdf

17:20 Discussion

Friday 6 May

15:00 → 19:00 Workshop Sessions: Session 4

15:00 AdePT integration ideas

• key integration goals
• constraints from external frameworks
• Geant4 interfacing approach
• current workflow limitatations

Speakers: Andrei Gheata (CERN), Witold Pokorski (CERN)

AdePTIntegrationHSF.pdf

15:30 Celeritas integration ideas

Experiment integration
- potential workflows
- challenges

Acceleritas: Celeritas/Geant4 integration
- offloading strategy and integration details
- theoretical and actual performance
- future work

Speakers: Soon Yung Jun (Fermi National Accelerator Lab. (US)), Stefano Tognini

4a-experiment-integration.pdf

4b-integration-acceleritas.pdf

16:00 Coffee break

16:20 AdePT perspectives

• summary of performance assessment and main bottlenecks
• further development ideas
• strategies, follow-ups and collaboration

Speakers: Andrei Gheata (CERN), Benjamin Morgan (University of Warwick (GB)), Witold Pokorski (CERN)

AdePTPerspectives.pdf

16:50 Celeritas perspectives

• summary of performance assessment and main bottlenecks
• further development ideas
• strategies, follow-ups and collaboration

Speaker: Seth Johnson (Oak Ridge National Laboratory)

5-conclusions-challenges.pdf

17:20 Final discussion