This example explores the parallelism provided by the topology of a graph. To make the results as predictable as possible, use a graph that is explicitly parallel, as shown below:

Because the

source_node

is serial, there is no parallelism provided from within the node. This ensures all parallelism observed is provided by the topology of the graph. Eight

source_nodes

are connected to a

join_node

and then to a

queue_node

. In this graph, only the

source_nodes

do useful work. Because the parallelism is solely from the topology of the graph, one item per

source_node

is enough to through the graph. Each

source_node

has a weight of 1s(1e6). The results of scalability analysis of the graph are shown below.

The speedup is directly proportional to the number of threads.