APPARATUS FOR CACHE CLEARING

摘要

A cache clearing apparatus for a multiprocessor data processing system having a cache unit and a duplicate directory associated with each processor. The duplicate directory, which reflects the contents of the cache directory within its associated cache unit, and the cache directory are connected through a system controller unit. Commands affecting information segments within the main memory are transferred by the system controller unit to each of the duplicate directories to determine if the information segment affected is stored in the cache memory of its associated cache memory. If the information segment is stored therein the duplicate directory issues a clear command through the system controller to clear the information segment from the associated cache unit. 5202766