A method and apparatus for a mechanism for handling explicit writeback in
a cache coherent multi-node architecture is described. In one embodiment,
the invention is a method. The method includes receiving a read request
relating to a first line of data in a coherent memory system. The method
further includes receiving a write request relating to the first line of
data at about the same time as the read request is received. The method
further includes detecting that the read request and the write request
both relate to the first line. The method also includes determining which
request of the read and write request should proceed first. Additionally,
the method includes completing the request of the read and write request
which should proceed first.