Reactive Systems and Microservices: Michael Mahoney Interview
ai.bythebay.io Nov 2025, Oakland, full-stack AI conference Scale By the Bay 2019 is held on November 13-15 in sunny Oakland, California, on the shores of Lake Merritt: https://scale.bythebay.io. Join us! ----- Michael W. Mahoney, UC Berkeley One of the important aspects about recent work in deep learning is that it is computationally-intensive in ways that most machine learning problems are not. This presents the opportunity to explore the productivity-performance in high performance/productivity computing, two areas that have developed in scientific computing and databases largely independently. Motivated by this, here, we explore the trade-offs of performing linear algebra for data analysis and machine learning using Apache Spark, compared to traditional C and MPI implementations on HPC platforms. Spark is designed for data analytics on cluster computing platforms with access to local disks and is optimized for data-parallel tasks. We examine three widely-used and important matrix factorizations: NMF (for physical plausibility), PCA (for its ubiquity) and CX (for data interpretability). We apply these methods to terabyte-sized problems in particle physics, climate modeling and bioimaging, as use cases where interpretable analytics is of interest. The data matrices are tall-and-skinny which enable the algorithms to map conveniently into Spark’s data-parallel model. We perform scaling experiments on up to 1600 Cray XC40 nodes, describe the sources of slowdowns, and provide tuning guidance to obtain high performance. We'll conclude with a discussion of recent work on…