The algorithm for executing graphs is actually very simple. Apibot first picks the starting node (which is the only node in the graph without predecessors), invokes the node’s function and then concurrently repeats this procedure for every successor of the current node.
In the image above, the
first node is executed first, followed by
second and finally
If a node has more than one predecessor, then the node will wait until all predecessors have been executed. In the image above, the two
third nodes will be executed concurrently (although not necessarily in parallel). When both
third nodes are executed then the
fourth will follow.