Scalable parallel programming in python with PArsL

Abstract

Python is increasingly the lingua franca of scientific computing. It is used as a higher level language to wrap lower-level libraries and to compose scripts from various independent components. However, scaling and moving Python programs from laptops to supercomputers remains a challenge. Here we present Parsl, a parallel scripting library for Python. Parsl makes it straightforward for developers to implement parallelism in Python by annotating functions that can be executed asynchronously and in parallel, and to scale analyses from a laptop to thousands of nodes on a supercomputer or distributed system. We examine how Parsl is implemented, focusing on syntax and usage. We describe two scientific use cases in which Parsl’s intuitive and scalable parallelism is used.