The performance of a particular probe-based storage device depends on its configuration and the workload that it is subject to. We can measure performance using a model of probe-based storage implemented in Pantheon, an I/O device simulator created by Hewlett-Packard [26,16]. We used this model to explore the behavior of probe-based storage under several workloads and identify a configuration with performance characteristics similar to disks [21]. However, the number of different configuration parameters is too large to use such a simulator to explore the design space exhaustively.
To address this problem, we created an analytical model that predicts the response time for various configurations. We make the simplifying assumption that requests are uniformly distributed across the device. This assumption does not hurt us as significantly as it would with disk drives because seek time is dominated by transfer time except at large degrees of parallelism [22]. Furthermore, as shown in [21], seek time is not as sensitive to other architectural parameters as transfer time.