Direct access storage device (DASD) modeling and validation

In a distributed environment where data are distributed and stored in individual DASDs, the performance of each of these DASD subsystems is critical to overall system performance. Hence, in order to size the DASD subsystems within a distributed environment appropriately, a flexible and robust planning tool is needed. A planning tool in the form of a robust simulation-based model is proposed for the performance evaluation of noncached and cached DASD subsystems. It is validated with performance data obtained from a real-world environment. This planning tool is part of an ongoing research project in the development of a four-level distributed information system simulator.<
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