A Query Processing Framework for Large-Scale Scientific Data Analysis

Abstract

Current scientific applications must analyze enormous amounts of array data using complex mathematical data processing methods. This paper describes a distributed query processing framework for large-scale scientific data analysis that captures array-based computations using SQL-like queries and optimizes and evaluates these computations using state-of-the-art parallel processing algorithms. Instead of providing a library of concrete distributed algorithms that implement certain matrix operations efficiently, we generalize these algorithms by making them parametric in such a way that the same efficient implementations that apply to the concrete algorithms can also apply to their generic counterparts. By specifying matrix operations as generic algebraic operators, we are able to perform inter-operator optimizations, such as fusing matrix transpose with matrix multiplication, resulting to new instantiations of the generic algebraic operators, without having to introduce new efficient algorithms on the fly. We report on a prototype implementation of our framework on three Big Data platforms: Hadoop Map-Reduce, Apache Spark, and Apache Flink, using Apache MRQL, which is a query processing and optimization system for large-scale, distributed data analysis. Finally, we evaluate the effectiveness of our framework through experiments on three queries: a matrix multiplication query, a simple query that combines matrix multiplication with matrix transpose, and a complex iterative query for matrix factorization.