Tracing the MPI-IO Calls' Disk Accesses

Thomas Ludwig, Stephan Krempel, Julian Kunkel, Frank Panse, Dulip Withanage


ABSTRACT

With parallel file I/O we are faced with the situation that we do not
have appropriate tools to get an insight into the I/O server behavior
depending on the I/O calls in the corresponding parallel MPI
program. We present an approach that allows us to also get event
traces from the I/O server environment and to merge them with the
client trace. Corresponding events will be matched and visualized. We
integrate this functionality into the parallel file system PVFS2 and
the MPICH2 tool Jumpshot.


KEYWORDS

Performance Analyzer, Parallel I/O, Visualization, Trace-based Tools, PVFS2