The SPARQLGX System for Distributed Evaluation of SPARQL Queries

SPARQL is the W3C standard query language for querying data expressed in the Resource Description Framework (RDF). The increasing amounts of data available in the RDF format raise a major need and research interest in building efficient and scalable distributed SPARQL query evaluators. In this context, we propose SPARQLGX: an implementation of a distributed RDF datastore based on Apache Spark. SPARQLGX is designed to leverage existing Hadoop infrastructures for evaluating SPARQL queries efficiently. SPARQLGX relies on an automated translation of SPARQL queries into optimized executable Spark code. We show that SPARQLGX makes it possible to evaluate SPARQL queries on billions of triples distributed across multiple nodes, while providing attractive performance figures. We report on experiments which show how SPARQLGX compares to state-of-the-art implementations and we show that our approach scales better than other systems in terms of supported dataset size. With its simple design, SPARQLGX represents an interesting alternative in several scenarios.