Journal Article

Model-based Performance Characterization of Software Correlators for Radio Interferometer Arrays

Fish, V. L., Ruszczyk, C. A., Elosegui, P., Lonsdale, C. J., Crew, G. B., Vázquez, A. J.

2022

Overview

Correlation for radio interferometer array applications, including Very Long Baseline Interferometry (VLBI), is a multidisciplinary field that traditionally involves astronomy, geodesy, signal processing, and electronic design. In recent years, however, high-performance computing has been taking over electronic design, complicating this mix with the addition of network engineering, parallel programming, and resource scheduling, among others. High-performance applications go a step further by using specialized hardware like Graphics Processing Units (GPUs) or Field Programmable Gate Arrays (FPGAs), challenging engineers to build and maintain high-performance correlators that efficiently use the available resources. Existing literature has generally benchmarked correlators through narrow comparisons on specific scenarios, and the lack of a formal performance characterization prevents a systematic comparison. This combination of ongoing increasing complexity in software correlation together with the lack of performance models in the literature motivates the development of a performance model that allows us not only to characterize existing correlators and predict their performance in different scenarios but, more importantly, to provide an understanding of the trade-offs inherent to the decisions associated with their design. In this paper, we present a model that achieves both objectives. We validate this model against benchmarking results in the literature, and provide an example for its application for improving cost-effectiveness in the usage of cloud resources.

• Publisher: The Astronomical Society of the Pacific,IOP Publishing
• Subject: Astronomy / Astronomy software / Correlation / Design / Distributed computing / Field programmable gate arrays / Geodesy / Interferometers / Interferometric correlation / Interferometry / Modelling / Radio astronomy / Radio interferometry / Software / Theoretical models