June 22–26, 2014
Leipzig, Germany

Presentation Details

Name: Rebasing I/O for Scientific Computing: Leveraging Storage Class Memory in an IBM BlueGene/Q Supercomputer
Time: Wednesday, June 25, 2014
03:15 pm - 03:45 pm
Room:   Hall 3
CCL - Congress Center Leipzig
Speaker:   Felix Schürmann, EPFL & Blue Brain Project
Abstract:   Storage class memory is receiving increasing attention for use in HPC systems for the acceleration of intensive IO operations. We report a particular instance using SLC FLASH memory integrated with an IBM BlueGene/Q supercomputer at scale (Blue Gene Active Storage, BGAS). We describe two principle modes of operation of the non-volatile memory: 1) block device; 2) direct storage access (DSA). The block device layer, built on the DSA layer, provides compatibility with IO layers common to existing HPC IO systems (POSIX, MPIO, HDF5) and is expected to provide high performance in bandwidth critical use cases. The novel DSA strategy enables a low-overhead, byte addressable, asynchronous, kernel by-pass access method for very high user space IOPs in multithreaded application environments. Here, we expose DSA through HDF5 using a custom file driver. Benchmark results for the different modes are presented and scale-out to full system size showcases the capabilities of this technology.

Felix Schürmann, EPFL; Fabien Delalondre, EPFL; Pramod S. Kumbhar, EPFL; John Biddiscombe, CSCS; Miguel Gila, CSCS; Davide Tacchella, CSCS; Alessandro Curioni, IBM Research; Bernhard Metzler, IBM Research; Peter Morjan IBM Germany Research & Development Lab; Joachim Fenkes, IBM Germany Research & Development Lab; Michele M. Franceschini, IBM T.J. Watson Research Center; Robert S. Germain, IBM T.J. Watson Research Center; Lars Schneidenbach, IBM T.J. Watson Research Center; T.J. Christopher Ward, IBM Software Group; Blake G. Fitch, IBM T.J. Watson Research Center