Measurement-based modeling and analysis methodology for characterizing parallel I/O performance

A parallel I/O characterization methodology that consists of a hierarchical modeling and measurement analysis environment for investigating I/O performance is presented. The methodology is illustrated via a case study of a video server workload running under the parallel I/O file system (PIOFS) of IBM SP/2. The measurements demonstrate that for video server and read-intensive workloads, spreading parallel files across all eight I/O servers improves a client's bandwidth performance by 36-52%. With eight clients, the per-client bandwidth performance increases by only 15%-23%. PIOFS-based default file striping results in degradation of bandwidth performance by as much as 25%.