Managing arbitrary distributions of arrays in Orléans Skeleton Library

Structured parallel models such as algorithmic skeletons offer a global view of the parallel program in contrast with the fragmented view of the SPMD style. This makes program easier to write and to read for users, and offer additional opportunities for optimisation done by the libraries, compilers and/or run-time systems. Algorithmic skeletons are or can be seen as patterns or higher-order functions implemented in parallel, often manipulating distributed data structures. Orléans Skeleton Library (OSL) is a library of parallel algorithmic skeletons, written in C++ on top of MPI, which uses meta-programming techniques for optimisation. Often such libraries have no or limited support for arbitrary distributions of the data structures. In this paper we detail the new OSL skeletons used to manage arbitrary distributions of distributed arrays. We present a parallel regular sampling sort application as an example of application that requires such skeletons.