Lawrence Berkeley National Laboratory Berkeley, United States of America
I/O on HPC systems is a black art. This tutorial sheds light on the state-of-the-art in parallel I/O and provides the knowledge necessary for attendees to best leverage I/O resources available to them. We cover the entire I/O software stack including storage and parallel file systems at the lowest layer, the role of burst buffers (NVRAM), intermediate layers (such as MPI-IO), and high-level I/O libraries (such as HDF-5). We emphasize ways to use these interfaces that result in high performance, and tools for generating insight into these stacks.
Our first third of the tutorial covers parallel I/O fundamentals. We discuss storage technologies, both present and near-future and the major parallel and distributed file systems. We focus on application in our second third, connecting storage to our examination of the upper library layers of the I/O stack; covering MPI-IO, Parallel netCDF and HDF5. Finally, we discuss tools for understanding I/O behavior.