SFIO, Parallel File Striping for MPI-I/O Emin Gabrielyan EPFL, Computer Science Dept. Peripheral Systems Lab. Emin.Gabrielyan@epfl.ch Abstract This paper presents the design and evaluation of a Striped File I/O (SFIO) library for parallel I/O in an MPI environment. We present techniques for optimizing communications and disk accesses for small striping factors. Using MPI derived datatype capabilities, we transmit fragmented data over the network by single MPI transfers. We present first results regarding the I/O performance of the SFIO library on DEC Alpha clusters, both for the Fast Ethernet and for the TNet Communication networks.