MPI-IO/Gfarm: An Optimized Implementation of MPI-IO for the Gfarm File System

This paper proposes a design and implementation of an MPI-IO implementation of the Gfarm file system, called MPI-IO/Gfarm. The Gfarm file system is a global file system that federates the local storage of compute nodes among several clusters. It has a scale-out architecture designed to support distributed data-intensive computing. However Gfarm file system does not achieve scalable performance in the case of parallel writes to a single file, a typical file operation in MPI-IO. This paper proposes an optimization technique to improve the parallel write performance to a single file. In the evaluation, MPI-IO/Gfarm achieves scalable parallel I/O performance.