Understanding Data Movement Patterns in HPC: A NERSC Case Study

Scientific experiments are producing unprecedented volumes of data with real-time High Performance Computing (HPC) needs. Understanding and ensuring efficient data movement in these emerging data-intensive workloads is becoming critical for successful workflow execution. The need for end-to-end that integrates compute, network, and storage resources across facilities is resulting in a new integrated infrastructure paradigm. In this paper, we present an extensive analysis of three years of network traffic data from NERSC and identify critical data movement trends while detecting bottlenecks that significantly curtail transfer performance. Our results show that data movement patterns have shifted in the three years, and current infrastructure cannot sufficiently handle competing transfers, leading up to 30% throughput degradation for individual flows. In addition, we provide design recommendations for data movement management in future integrated research infrastructures that aim to reduce data transfer latency, reducing overall time to scientific results.