Thematic CERN School of Computing on Scientific Software for Heterogeneous Architectures

Name: Thematic CERN School of Computing on Scientific Software for Heterogeneous Architectures
Start: 2025-10-05T15:00:00+02:00
End: 2025-10-11T11:30:00+02:00
Location: Medils Institute, Split

5 Oct 2025, 15:00 → 11 Oct 2025, 11:30 Europe/Zagreb

Medils Institute, Split

Meštrovićevo šetalište 45 HR – 21000 Split Croatia

Alberto Pace (CERN), Kristina Gunne (CERN), Andrzej Nowicki (CERN)

Description

The 18^th Thematic CERN School of Computing (tCSC 2025) will take place on October 5-11, 2025. The theme of the school is "Scientific Software for Heterogeneous Architectures" - see the academic programme for more details.

This school is organized by CERN in collaboration with the Faculty of Science, University of Split. The school will take place in Split, Croatia, and be hosted at the Mediterranean Institute for Life Sciences (MEDILS) Conference Centre. The Centre is a historical renovated building situated in a wooded and landscaped park located on the Adriatic Sea coast, a few kilometers from the center of Split.

Target Audience

The School is aimed at postgraduate (i.e. a minimum of Bachelor's degree or equivalent) students, engineers, and scientists with a few years of experience in particle physics, in computing, or in related fields. We welcome applications from all countries and nationalities.

Important dates

14 May application opens
10 July application close
23 July invitations sent to selected students
20 August confirmation of participation deadline
3 September participation fee deadline

CERN School of Computing

Computing.School@cern.ch

Registration

Applications

Sunday 5 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 15:00 → 16:00
  
  Registration 1h
- 16:00 → 16:20
  
  Welcome and introduction 20m
- 16:20 → 17:00
  
  Self presentations 40m
  
  One minute-one slide self presentations
- 17:00 → 17:30
  
  Transport to Split 30m
- 17:30 → 18:45
  
  Guided tour of Split 1h 15m
- 19:30 → 21:00
  
  Welcome dinner at Restoran Para di šoto 1h 30m
Monday 6 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 07:45 → 08:45
  
  Breakfast 1h Medils
  
  Medils
- 08:45 → 09:45
  
  Opening Session 1h
  
  Speaker: Alberto Pace (CERN)
- 09:45 → 10:45
  
  Preparing for the HL-LHC computational challenge 1h
  
  In this talk we will introduce some basic concepts related to HEP data processing and analysis workflows, seeing them in action in the context of LHC experiments. We’ll also talk about the evolution of the LHC accelerator and experiments. We’ll characterise at a high level what are the consequences of those upgrades for the HEP data processing software, in particular in the context of an evolving hardware and computing infrastructure.
  
  Speaker: Danilo Piparo (CERN)
- 10:45 → 11:00
  
  Announcements 15m
- 11:00 → 11:30
  
  Break 30m
- 11:30 → 12:30
  CPU Hardware Architecture and Evolution 1h
  CPU Architecture and High Performance - lecture 1
  - Hardware evolution of the CPU
  - Memory hierarchy, caching, NUMA
  - Microarchitecture of modern CPUs
  Speaker: Guilherme Amadio (CERN)
- 12:30 → 13:30
  Performance Analysis on Modern CPUs 1h
  CPU Architecture and High Performance - lecture 2
  - Performance analysis tools for Linux
  - CPU features for performance analysis
  - Top-down microarchitecture analysis
  Speaker: Guilherme Amadio (CERN)
- 13:30 → 14:30
  
  Lunch 1h
- 14:30 → 16:00
  
  Study or Sports time 1h 30m
- 16:00 → 16:30
  
  Break 30m
- 16:30 → 17:30
  
  CPU Architecture and High Performance - exercise 1 1h
  
  Speaker: Guilherme Amadio (CERN)
- 17:30 → 18:15
  
  Student lightning talks 45m
- 19:30 → 20:30
  
  Dinner 1h
  
  Francuska 7, Belgrade 11000, Serbia
Tuesday 7 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 07:45 → 08:45
  
  Breakfast 1h
- 08:45 → 09:45
  Writing parallel software 1h
  Parallel and Optimised Scientific Software - lecture 1
  - Amdahl's and Gustafson's laws
  - Asynchronous execution
  - Finding concurrency, task vs. data parallelism
  - Using threading in C++ and Python, comparison with multi-process
  - Resource protection and thread safety
  - Locks, thread local storage, atomic operations
  Speaker: Sebastien Ponce (CERN)
- 09:45 → 10:45
  Writing efficient software 1h
  Parallel and Optimised Scientific Software - lecture 2
  - Why Python and C++ ?
  - Recent evolutions: C++ 11/14/17
  - Modern features of C++ related to performance
  - Templating versus inheritance, pros and cons of virtual inheritance
  - Python 3, and switching from Python 2
  Speaker: Sebastien Ponce (CERN)
- 10:45 → 11:00
  
  Announcements 15m
- 11:00 → 11:30
  
  Coffee break 30m
- 11:30 → 12:30
  Low-level Performance Optimization Guidelines 1h
  CPU Architecture and High Performance - lecture 3
  - Main sources of performance bottlenecks
  - Floating point arithmetics performance
  - Advanced low-level performance tuning
  Speaker: Guilherme Amadio (CERN)
- 12:30 → 13:30
  
  CPU Architecture and High Performance - exercise 2 1h
  
  Speaker: Guilherme Amadio (CERN)
- 13:30 → 14:30
  
  Lunch 1h
- 14:30 → 16:00
  
  Study or sports time 1h 30m
- 16:00 → 16:30
  
  Coffee break 30m
- 16:30 → 17:30
  Optimizing existing large codebase 1h
  Parallel and Optimised Scientific Software - lecture 3
  - Measuring performance, tools and key indicators
  - Improving memory handling
  - The nightmare of thread safety
  - Code modernization and low level optimizations
  - Data structures for efficient computation in modern C++
  Speaker: Sebastien Ponce (CERN)
- 17:30 → 18:30
  
  Data-Oriented Design 1h
  
  CPU Architecture and High Performance - lecture 4
  - Principles of data-oriented design
  - Memory access and data-type profiling
  - Data structure performance optimization
  
  Speaker: Guilherme Amadio (CERN)
- 18:30 → 19:30
  
  Managing Large Databases: Challenges and Lessons 1h
  
  With around 100 Oracle databases and several PB of data, CERN faces numerous intriguing challenges and unique caveats in regards to managing the database infrastructure. This lecture aims to provide an overview of both past and current issues and obstacles encountered in the realm of database systems at CERN. By doing so, it seeks to offer valuable insights into potential problems to avoid and effective solutions to address encountered difficulties.
  
  Speaker: Andrzej Nowicki (CERN)
- 19:30 → 20:30
  
  Dinner 1h
Wednesday 8 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 07:45 → 08:45
  
  Breakfast 1h
- 08:45 → 09:45
  Scientific computing on heterogeneous architectures 1h
  Programming for Heterogeneous Architectures - lecture 1
  - Introduction to heterogeneous architectures and the performance challenge
  - From general to specialized: Hardware accelerators and applications
  - Type of workloads ideal for different accelerators
  - Trade-offs between multi-core and many-core architectures
  - Implications of heterogeneous hardware on the design and architecture of scientific software
  - Embarrassingly parallel scientific applications in HPC and CERN
  Speaker: Daniel Hugo Campora Perez (NVIDIA)
- 09:45 → 10:45
  
  Optimizing existing large codebase - exercise 1 1h
  
  Optimisation of an existing, production grade large codebase
  
  Speaker: Sebastien Ponce (CERN)
- 10:45 → 11:00
  
  Announcements 15m
- 11:00 → 11:15
  
  Coffee break 15m
- 11:15 → 12:15
  
  Optimizing existing large codebase - exercise 2 1h
  
  Optimisation of an existing, production grade large codebase
  
  Speaker: Sebastien Ponce (CERN)
- 12:15 → 13:00
  
  Lunch 45m
- 13:00 → 18:00
  
  River rafting excursion - Cetina River 5h
- 18:30 → 20:30
  
  Dinner at Kastel Slanica Omis 2h
- 20:30 → 21:30
  
  Transport to Medils 1h
Thursday 9 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 07:45 → 08:45
  
  Breakfast 1h
- 08:45 → 09:45
  Performant programming for GPUs 1h
  Programming for Heterogeneous Architectures - lecture 2
  - From SIMD to SPMD, a programming model transition
  - Thread and memory organization
  - Basic building blocks of a GPU program
  - Control flow, synchronization, atomics
  Speaker: Daniel Campora (NVIDIA)
- 09:45 → 10:45
  Performant programming for GPUs 1h
  Programming for Heterogeneous Architectures - lecture 3
  - Data locality, coalesced memory accesses, tiled data processing
  - GPU streams, pipelined memory transfers
  - Under the hood: branchless, warps, masked execution
  - Debugging and profiling a GPU application
  Speaker: Daniel Campora (NVIDIA)
- 10:45 → 11:00
  
  Announcements 15m
- 11:00 → 11:30
  
  Coffee break 30m
- 11:30 → 12:30
  Practical vectorization 1h
  Parallel and Optimised Scientific Software - lecture 4
  - Measuring vectorization level
  - What to expect from vectorization
  - Preparing code for vectorization
  - Vectorizing techniques in C++: intrinsics, libraries, autovectorization
  Speaker: Sebastien Ponce (CERN)
- 12:30 → 13:30
  
  Practical vectorization - exercise 1h
  
  Speaker: Sebastien Ponce (CERN)
- 13:30 → 14:30
  
  Lunch 1h
- 14:30 → 16:30
  
  Study time or sports 2h
- 16:30 → 17:00
  
  Coffee break 30m
- 17:00 → 18:00
  
  Programming for heterogeneous architectures - exercise 1h
  
  Speaker: Daniel Campora (NVIDIA)
- 18:00 → 19:00
  
  Programming for heterogeneous architectures - exercise 1h
  
  Speaker: Daniel Campora (NVIDIA)
- 19:30 → 20:30
  
  Dinner 1h
Friday 10 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 07:45 → 08:45
  
  Breakfast 1h
- 08:45 → 09:45
  
  Debrief of exercises 1h
- 09:45 → 10:45
  Design patterns and best practices 1h
  Programming for Heterogeneous Architectures - lecture 4
  - Good practices: single precision, floating point rounding, avoid register spilling, prefer single source
  - Other standards: SYCL, HIP, OpenCL
  - Middleware libraries and cross-architecture compatibility
  - Reusable parallel design patterns with real-life applications
  Speaker: Daniel Campora (NVIDIA)
- 10:45 → 11:00
  
  Announcements 15m
- 11:00 → 11:30
  
  Coffee break 30m
- 11:30 → 12:30
  
  Programming for heterogeneous architectures - exercise 1h
  
  Speaker: Daniel Campora (NVIDIA)
- 12:30 → 13:30
  
  Programming for heterogeneous architectures - exercise 1h
  
  Speaker: Daniel Campora (NVIDIA)
- 13:30 → 14:30
  
  Lunch 1h
- 14:30 → 15:45
  
  Exam 1h 15m
- 15:45 → 16:20
  
  Coffee break 35m
- 16:20 → 17:20
  
  Closing Session 1h
- 17:20 → 19:20
  
  Free time 2h
- 19:30 → 21:30
  
  Closing dinner Kavanazona 2h
Saturday 11 October
- Sun 5 Oct
- Mon 6 Oct
- Tue 7 Oct
- Wed 8 Oct
- Thu 9 Oct
- Fri 10 Oct
- Sat 11 Oct
- 07:30 → 08:30
  
  Breakfast 1h
- 09:00 → 11:30
  
  Departures 2h 30m