An exemplary embodiment of the invention is a method for providing a path-sensitive
branch registry for cyclic distributed transactions. This method requires that
a superior node's transaction manager (TM) identify itself as the root followed
by sending the syncpoint cue to at least one subordinate node. Before sending the
syncpoint cues to the subordinate the superior links the inbound messages with
its specific branch qualifier (BQUAL) as well as a global transaction identifier
(GTRID). The TM of each subordinate node receives syncpoint cues and is responsible
for knowing who its superior is. In addition, the TM is responsible for recognizing
the flow of branch instructions and guarantee that it uses a network-wide unique
value for the branch values it generates for a given global transaction. With the
recognition of the flow from the superior node the subordinate TM updates the node
registry as to the inbound and outbound flow of branch messages by its superior
and its subordinates.
