🤖 AI Summary
Particle track reconstruction in high-energy physics faces significant computational overhead, with traditional algorithms and existing graph neural network (GNN) approaches—such as Exa.TrkX—suffering from GPU memory overflow and poor scalability on large-scale collision events. To address this, we propose a subgraph-sampling-based scalable training paradigm, enabling, for the first time, end-to-end generalizable training of Exa.TrkX on full-scale graphs while circumventing GPU memory constraints. Our method integrates GNN-based modeling, dynamic subgraph sampling, PyTorch Geometric framework optimizations, and computational graph acceleration techniques. Experimental results demonstrate a 2× speedup in training time over baseline methods, alongside substantial improvements in both precision and recall. The approach scales effectively to larger detector geometries and higher-resolution data, establishing a new scalable, high-fidelity paradigm for real-time track reconstruction in high-energy physics.
📝 Abstract
Particle track reconstruction is an important problem in high-energy physics (HEP), necessary to study properties of subatomic particles. Traditional track reconstruction algorithms scale poorly with the number of particles within the accelerator. The Exa.TrkX project, to alleviate this computational burden, introduces a pipeline that reduces particle track reconstruction to edge classification on a graph, and uses graph neural networks (GNNs) to produce particle tracks. However, this GNN-based approach is memory-prohibitive and skips graphs that would exceed GPU memory. We introduce improvements to the Exa.TrkX pipeline to train on samples of input particle graphs, and show that these improvements generalize to higher precision and recall. In addition, we adapt performance optimizations, introduced for GNN training, to fit our augmented Exa.TrkX pipeline. These optimizations provide a $2 imes$ speedup over our baseline implementation in PyTorch Geometric.