DONIO: Distributed Object Network I/O Library

Abstract

This manuscript describes the implementation of DONIO (Distributed Object Network I/O), a library of routines that provide fast non-sequential file I/O capabilities in the Intel iPSC/860 and Paragon distributed memory parallel environments. DONIO caches a copy of the file in memory distributed across all processors. Disk I/O routines (such as read, write, and lseek) are replaced by calls to DONIO routines, which translate these operations into message communication to update the cached data. Experiences with an application on seismic data analysis on the Intel Paragon show that the cost of concurrent disk I/O using DONIO for large files can be 5 times smaller than using standard disk I/O. 1 Introduction Multi-megabyte disk input/output operations are commonly a major bottleneck in large application codes on distributed memory parallel supercomputers. This report describes the first version of the Distributed Network I/O (DONIO) library routines, 1 which provide fast parallel non-s..