Introduction

• Philippe Gras (Université Paris-Saclay (FR))

Experience from porting VecGeom to Julia

• Pere Mato Vila (CERN)

Pere evaluated Julia on a common HEP use case of detector geometry description. VecGeom C++ package has been partially reimplemented in Julia and performance were compared with the C++ version. Project Github repository: <a href="https://github.com/peremato/Geom4hep">Geom4hep</a>

Evaluation of the Julia language based on a fastjet algorithm

• Philippe Gras (Université Paris-Saclay (FR))

The Julia language has been evaluated for highly optimized fast jet algorithms from [fastjet](Evaluation of the Julia language based on a fastjet algorithm). The exercise has been lead in parallel by two persons. Github repositories: <a href="https://github.com/gojakuch/JetReconstruction.jl">JetReconstruction.jl</a> and <a href="https://github.com/grasph/AntiKt.jl">Antikt.jl</a>. See also Atell-Yehor Krasnopolski's <a href="https://indico.cern.ch/event/1195272/contributions/5064323/attachments/2518088/4329524/IRIS-HEP-final-presentation-AtellKrasnopolski.pdf">presentaion</a> at IRIS-hep

Experience from UnROOT development on type stability and performance optimization for HEP data

• Jerry 🦑 Ling (Harvard University (US))

<a href="https://github.com › JuliaHEP › UnROOT.jl">UnROOT</a> is a package written fully in Julia to read ROOT files. It is very fast. The secret used to handle in inhomogeneous columnar data with high performance will be explained. Challenges in optimizing the code will be discussed.

Code review (TBC) The programming code from Geom4hep and Fastjet exercises has been reviewed. Hints for improving their performance will be suggested.

Discussion: conclusions to draw for the report and possible home work Discussion about the conclusions to draw for being included in the report and possibly some next steps to understand differences observed between Julia and C++.