Smart read/write for MPI-IO

We present a case for automating the selection of MPI-IO performance optimizations, with an ultimate goal to relieve the application programmer from these details, thereby improving their productivity. Programmers productivity has always been overlooked as compared to the performance optimizations in high performance computing community. In this paper we present RFSA, a reduced function set abstraction based on an existing parallel programming interface (MPI-IO) for I/O. MPI-IO provides high performance I/O function calls to the scientists/engineers writing parallel programs; who are required to use the most appropriate optimization of a specific function, hence limits the programmer productivity. Therefore, we propose a set of reduced functions with an automatic selection algorithm to decide what specific MPI-IO function to use. We implement a selection algorithm for I/O functions like read, write, etc. RFSA replaces 6 different flavors of read and write functions by one read and write function. By running different parallel I/O benchmarks on both medium-scale clusters and NERSC supercomputers, we show that RFSA functions impose minimal performance penalties.