This paper describes an approach to track, compress and replay I/O calls from a parallel application. We will introduce our method to capture calls to POSIX I/O functions and to create I/O dependency graphs for parallel program runs. The resulting graphs will be compressed by a pattern matching algorithm and used as an input for a flexible I/O benchmark. The first parts of the paper cover the information gathering and compression in the area of POSIX I/O while the later parts are dedicated to the I/O benchmark and to some results from experiments.