PERFORMANCE ATTRIBUTES FOR CODE AND WORKLOAD ANALYSIS ON CRAY X-MP AND Y-MP SYSTEM

A Performance Analysis Tools (PAT) report implementing hpm and perftra ce software, installed under UNICOS on CRAY X-MP and Y-MP systems, was designed at the Ohio Supercomputer Center. The report presents a conc ise summary of code performance characteristics using 28 performance a ttributes grouped into four categories: operations and instructions, s calar to vector load balance, memory utilization, and input/output uti lization. Demonstrated applications of this performance metric include code performance analysis in a case study, workload analysis for a 24 -code sample, and performance comparison of CRAY X-MP and Y-MP process ors. The analysis of the case study shows that a precise performance a ssessment was possible using this metric without the necessity of sour ce code analysis. Measurements with the 24-code sample established rea listic performance ranges in the metric and were also used to compare performance of CRAY X-MP and Y-MP models. Although the clock period on the Y-MP was reduced by 29% relative to the X-MP, increases of 52% we re observed in instruction fetch rates and vector MFLOPS, with a corre sponding rise of 39% in computational intensity.