A Black Box Model for Storage Devices Based on Probability Distributions

Traditional approaches for storage devices simulation have been based on detailed analytical models. However, detailed models require detailed computations which may be not affordable for large scale simulations. Moreover, highly detailed models cannot be easily generalized. A different approach is the black-box statistical modeling, where the storage device, its interface, and the interconnection mechanisms are modeled as a single stochastic process, defining the request response time as a random variable with an unknown distribution. A random variate generator can be built and integrated into a simulation model. This approach allows to generate a simulation model for both real and synthetic workloads. This article describes a method suitable for building fast simulation models for storage devices. Our method uses as starting point a workload and produces a random variate generator which can be easily integrated into large scale simulation models. A comparison between our variate generator and the widely known simulation tool DiskSim, shows that our variate generator is faster, and can be as accurate as DiskSim.