A method and apparatus for filtering memory probe activity for writes in a
distributed shared memory computer. In one embodiment, the method may
include assigning an uncached directory state to a cache data block in
response to evicting the cache data block. In another embodiment, the
method may include assigning a remote directory state to a cache data
block in response to evicting the cache data block and storing it in a
remote cache. In a third embodiment, the method may include assigning a
pairwise-shared directory state in response to a second processor node
initiating a load operation to a cache data block in a modified cache
state in a first processor node. In a fourth embodiment, the method may
include assigning a migratory directory state in response to a processor
node initiating a store operation to a cache data block in a
pairwise-shared cache state.