DONIO: Distributed Object Network I/O Library

This report describes the use and implementation of DONIO (Distributed Object Network I/O), a library of routines that provide fast 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. Experiments on the Intel Paragon show that the cost of concurrent disk I/O using DONIO for large files can be 15-30 times smaller than using standard disk I/O.