Abstract: An apparatus, system and method of verifying data are provided. Active data are identified among data on a storage device, records the location of the active data, and the integrity of the active data are verified. In one embodiment, data in segments adjacent to the active data segments are also identified and verified for improved data reliability. The data verification may be used to increase data reliability with low system resource usage.

Abstract: A process, apparatus, and system for evaluating a projected cache size implement and manage one or more projected cache lists that each contains directory entries corresponding to a projected cache size. The projected cache size may be either smaller or larger than the actual size of a cache installed in a computer system. Using the projected cache list entries, performance statistics such as cache hit ratio and average access time are tracked for each list. The process, apparatus, and system may calculate performance parameters that describe the performance specific to the actual cache list and each projected cache list. The resulting performance statistics may be used to formulate an optimization parameter to be communicated to a user or an administrator application.