NPAC Technical Report SCCS-564

Design and Evaluation of Primitives for Parallel I/O

Rajesh Bordawekar, Juan Miguel del Rosario, Alok Choudhary

Submitted November 1 1993


Abstract

In this paper, we show that the performance of parallel file systems can vary greatly as a function of the selected data distributions, and that some data distributions can not be supported. We have devised an alternative scheme for conducting parallel I/O - the Two-Phase Access Strategy - which guarantees higher and more consistent performance over a wider spectrum of data distributions. We have designed and implemented runtime primitives that make use of the two-phase access strategy to conduct parallel I/O, and facilitate the programming of parallel I/O operations. We describe these primitives in detail and provide performance results which show that I/O access rates are improved by up to several orders of magnitude. Further, we show that the variation in performance over various data distributions is restricted to within a factor of 2 of the best access rate.


PostScript version of the paper