Communication overhead for space science applications on theBeowulf parallel workstation

摘要

The Beowulf parallel workstation combines 16 PC-compatibleprocessing subsystems and disk drives using dual Ethernet networks toprovide a single-user environment with 1 Gops peak performance, half aGbyte of disk storage, and up to 8 times the disk I/O bandwidth ofconventional workstations. The Beowulf architecture establishes a newoperating point in price-performance for single-user environmentsrequiring high disk capacity and bandwidth. The Beowulf research projectis investigating the feasibility of exploiting mass market commoditycomputing elements in support of Earth and space science requirementsfor large data-set browsing and visualization, simulation of naturalphysical processes, and assimilation of remote sensing data. This paperreports the findings from a series of experiments for characterizing theBeowulf dual channel communication over-head. It is shown that dualnetworks can sustain 70% greater throughput than a single network alonebut that bandwidth achieved is more highly sensitive to message sizethan to the number of messages at peak demand. While overhead is shownto be high for global synchronization, its overall impact on scalabilityof real world applications for computational fluid dynamics and N-bodygravitational simulation is shown to be modest