Insight through simplicity

摘要

As I/O subsystems and storage devices grow in complexity, simple models, while not always accurate enough to calibrate to measurements, are of great value to enhance our understanding of important performance factors of these systems. This paper considers simple models of cached I/O, Parallel Access Volumes and hypervolumes, as well as the communication fabric of a Storage Area Network to illustrate this point. An example shows also how simple models can guide our understanding of actual measurement data and help in the subsequent model calibration.