A multiprocessing node in a snooping-based cache-coherent cluster of
processing nodes maintains a cache-to-cache transfer prediction directory
of addresses of data last transferred by cache-to-cache transfers. In
response to a local cache miss, the multiprocessing node may use the
cache-to-cache transfer prediction directory to predict a cache-to-cache
transfer and issue a restricted broadcast for requested data that allows
only cache memories in the cluster to return copies of the requested data
to the requesting multiprocessing node, thereby reducing the consumption
of bandwidth that would otherwise be consumed by having a home memory
return a copy of the requested data in response to an unrestricted
broadcast for requested data that allows cache memories and home memories
in a cluster to return copies of the requested data to the requesting
multiprocessing node.