@InProceedings{worringen:non-contiguous, author = {Joachim Worringen and Jesper Larson Tr\"{a}ff and Hubert Ritzdorf}, title = {Fast Parallel Non-Contiguous File Access}, booktitle = {Proceedings of SC2003: High Performance Networking and Computing}, year = {2003}, month = {November}, publisher = {IEEE Computer Society Press}, address = {Phoenix, AZ}, URL = {http://www.sc-conference.org/sc2003/paperpdfs/pap319.pdf}, keywords = {parallel I/O interface, file access patterns, pario-bib}, abstract = {Many applications of parallel I/O perform non-contiguous file accesses, but only few file system interfaces support non-contiguous access. In contrast, the most commonly used parallel programming interface, MPI, supports parallel I/O through its MPI-IO interface. Within this interface, non-contiguous accesses are supported by the use of derived MPI datatypes. Unfortunately, current MPI-IO implementations suffer from low performance of such non-contiguous accesses when compared to the performance of the storage system for contiguous accesses although a considerable amount of work has been done in this area. In this paper we analyze an important bottleneck in current implementations of MPI-IO, and present a new technique termed listless i/o to perform non-contiguous access with MPI-IO. On the NEC SX-series of parallel vector computers, listless i/o is able to increase the bandwidth for non-contiguous file access by sometimes more than a factor of 500 when compared to the traditional approach.}, comment = {published on the web} }