Computer Engineering Commons^™

Scalable Implementations Of Mpi Atomicity For Concurrent Overlapping I/O, Wei-Keng Liao, Alok Choudhary, Kenin Coloma, George K. Thiruvathukal, Lee Ward, Eric Russell, Neil Pundit

George K. Thiruvathukal

For concurrent I/O operations, atomicity defines the results in the overlapping file regions simultaneously read/written by requesting processes. Atomicity has been well studied at the file system level, such as POSIX standard. In this paper, we investigate the problems arising from the implementation of MPI atomicity for concurrent overlapping write access and provide a few programming solutions. Since the MPI definition of atomicity differs from the POSIX one, an implementation that simply relies on the POSIX file systems does not guarantee correct MPI semantics. To have a correct implementation of atomic I/O in MPI, we examine the efficiency of three …