RIOT: I/O efficient numerical computing without SQL

Abstract

R is a numerical computing environment that is widely popular for statistical data analysis. Like many such environments, R performs poorly for large datasets whose sizes exceed that of physical mem- ory. We present our vision of RIOT(R with I/O Transparency), a system that makes R programs I/O-efficient in a way transpar- ent to the users. We describe our experience with RIOT-DB, aninitial prototype that uses a relational database system as a back- end. Despite the overhead and inadequacy of generic database sys- tems in handling array data and numerical computation, RIOT-DB significantly outperforms R in many large-data scenarios, thanks to a suite of high-level, inter-operation optimizations that integrate seamlessly into R. While many techniques in RIOT are inspired by databases (and, for RIOT-DB, realized by a database system), RIOT users are insulated from anything database related. Compared with previous approaches that require users to learn new languages and rewrite their programs to interface with a database, RIOT will, we believe, be easier to adopt by the majority of the R user.