Java2SDG: Stateful big data processing for the masses

Big data processing is no longer restricted to specially-trained engineers. Instead, domain experts, data scientists and data users all want to benefit from applying data mining and machine learning algorithms at scale. A considerable obstacle towards this “democratisation of big data” are programming models: current scalable big data processing platforms such as Spark, Naiad and Flink require users to learn custom functional or declarative programming models, which differ fundamentally from popular languages such as Java, Matlab, Python or C++. An open challenge is how to provide a big data programming model for users that are not familiar with functional programming, while maintaining performance, scalability and fault tolerance. We describe JAVA2SDG, a compiler that translates annotated Java programs to stateful dataflow graphs (SDGs) that can execute on a compute cluster in a data-parallel and fault-tolerant fashion. Compared to existing distributed dataflow models, a distinguishing feature of SDGs is that their computational tasks can access distributed mutable state, thus allowing SDGs to capture the semantics of stateful Java programs. As part of the demonstration, we provide examples of machine learning programs in Java, including collaborative filtering and logistic regression, and we explain how they are translated to SDGs and executed on a large set of machines.