For the 2026 workshop, there will be 3 different projects. In the projects listed below, students will work in pairs and with their mentors who will oversee their project. The mentors are all established scientists at Los Alamos National Laboratory.
Chemical Kinetics for Exascale Particle-In-Cell Simulations
Nigel Tan, XCP-6, Ari Le, XCP-6, and Adam Stanier, T-5
Developing large scale multiphysics simulations requires many different physics components working together. Each component often has different time step sizes, mesh resolutions, performance properties, and scalability characteristics. You will work with physicists and HPC experts on porting an atmospheric air chemistry code from Python to C++ and parallelize it across different CPUs and GPUs using the Kokkos performance portability ecosystem. The air chemistry code will then be coupled with the Hybrid Vector Particle-In-Cell (VPIC) code as part of the Multiphysics Artificial Radiation Belt and E3 Electro-Magnetic Pulse High-Altitude Nuclear Explosion End-to-End Model (MAEHEM) project. You will gain valuable experience porting Python code to CPU and GPU based HPC platforms such as Rocinante, Chicoma, and Venado like systems. You will also learn about running multiphysics simulations on different HPC resources, using different profilers to identify performance bottlenecks, benchmarking code on a variety of different platforms, and how scientists turn research prototypes into practical production code.
Accessing the Exascale: Enabling Scalable GPU-Accelerated Multiphysics on Hybrid Architectures
Michael Witek, XCP-2 and Kyle Vaughn, XCP-2
Pagosa is a 3-D Eulerian hydrodynamics code that models phenomena associated with highvelocity impacts and explosively driven systems. Recent modernization efforts have enabled strong scaling to hundreds of nodes, but the code remains MPI-only. This limits its performance on hybrid CPU-GPU systems, e.g., LLNL’s El Capitan, which contains AMD MI300A APUs and has been verified as the world’s fastest supercomputer at 1.743 exaFLOPs, and LANL’s upcoming Mission and Vision systems that will be based on the NVIDIA Vera Rubin platform. With an MPI-only parallelization scheme, internal benchmarks have shown a performance bottleneck: as MPI ranks increase, they contend with a small set of GPUs, reducing overall efficiency. In this project, students will explore a hybrid MPI + OpenMP approach to solve the GPU contention problem. The students will develop benchmarks that demonstrate the feasibility of using a few MPI ranks to manage pools of OpenMP threads and communicate with GPUs. The students will then work to incorporate the scheme into the Pagosa codebase. Interested students should be proficient in modern C++ and will gain valuable experience with state-of-the-art HPC tools and modern software-engineering workflows for a large production code that runs on the world’s fastest supercomputers.
Active Learning of Phase Diagrams of Mixtures
Leonid Burakovsky, T-1 and Dean Preston, XCP-5
Mapping vast composition spaces of multi-component mixtures through experiments is too slow. A computational alternative is proposed. It consists in combining the underlying theory with ab initio quantum molecular dynamics (QMD) simulations using high-performance computing (HPC) at Los Alamos, to autonomously explore and model phase/property landscapes of multi-component mixtures within several weeks. For the QMD simulations the software VASP (Vienna Ab initio Simulation Package) installed on all the HPC clusters on which the principal investigator (PI) has an account, such as Chicoma, will be used.
Performance Profiling and Improvements for Large Multiphysics Simulations - Shaped Charges
CJ Solomon (XCP-2) and Matt Wilson (XCP-2)
Students will profile and improve the performance of the Eulerian Applications Project’s production code xRAGE. Students will profile and identify hotspots on the LANL HPC system Rocinante when using xRAGE’s on node OpenMP parallel computing capabilities. Depending on machine availability, they will also profile xRAGe on LANL’s Nvidia Grace+Hopper developmental cluster, Venadito. In addition to profiling experience, students will gain familiarity with C++ based performance portability layers, similar to the Linux Foundation’s Kokkos project, and develop an appreciation for the level of software engineering a production product such as xRAGE requires. This project will focus on improving the performance of a high explosive driven shaped charge.
Performance Profiling and Improvements for Large Multiphysics Simulations - ICF Capsules
Thomas Vogel (CAI-1) and Pete Maginot (XCP-2)
Students will profile and improve the performance of the Eulerian Applications Project’s production code xRAGE. Students will profile and identify hotspots on the LANL HPC system Rocinante when using xRAGE’s on node OpenMP parallel computing capabilities. Depending on machine availability, they will also profile xRAGe on LANL’s Nvidia Grace+Hopper developmental cluster, Venadito. In addition to profiling experience, students will gain familiarity with C++ based performance portability layers, similar to the Linux Foundation’s Kokkos project, and develop an appreciation for the level of software engineering a production product such as xRAGE requires. This project will focus on improving the performance of an ICF capsule simulation.