Analyzing the I/O behavior of supercomputer applications

Supercomputer applications of I/Os are classified here into three categories - required, checkpoint, and data staging - and it is shown how memory size and CPU speed are likely to affect each category. A data analysis shows that data staging I/O dominates when it is present. If an application requires data staging I/O, its read/write ratio is greater than one; otherwise, its read/write ratio is less than one. This information can be used to anticipate a program's I/O demands and thus reduce the load on the I/O system.