Abstract
Given the growing disparity between CPU power and the speed of secondary storage, a data cache exploiting large processor storage has the potential to improve response time dramatically in many situations. The VM/XA SP2 minidisk cache facility, the result of research activity on the characteristics of interactive file-system activity, uses expanded storage to cache input/output to minidisks on the Conversational Monitor System. The size of the cache is dynamically adjusted by an arbitration process to optimize system performance. Several other functions improve the performance of the cache during periods of unusual I/O loads.