Cache coherence directory eviction mechanisms for modified copies of memory lines in multiprocessor systems

摘要

Cache coherence directory eviction mechanisms are described for use in computer systems having a plurality of multiprocessor clusters. Interaction among the clusters is facilitated by a cache coherence controller in each cluster. A cache coherence directory is associated with each cache coherence controller identifying memory lines associated with the local cluster which are cached in remote clusters. The cache coherence controller is operable to initiate eviction of an entry in its directory corresponding to a modified copy of a memory line by sending a request to merge an empty data field with the modified copy of the memory line to a corresponding memory controller.