Drive-Thru: fast, accurate evaluation of storage power management
Daniel Peek, Jason Flinn · 2005
Running traces of realistic user activity is an important step in evaluating storage power management. Unfortunately, existing methodologies that replay traces as fast as possible on a live system cannot be used to evaluate timeout-based power management policies. Other methodologies that slow down replay to preserve the recorded delays between operations are too timeconsuming. We propose a hybrid approach, called Drive-Thru, that provides both accuracy and speed of evaluation by separating time-dependent and time-independent activity. We first synchronously replay file system activity on the target platform to create a base trace that captures the semantic relationship between file system activity and storage accesses. We then use the base trace as input to a simulator that can evaluate different disk, network, file cache, and file system power management policies. We use Drive-Thru to study the benefit of several recent proposals to reduce file system energy usage. 1