Thus at step 5, the root sends the single problem to the worker node, who receives it. At step 9 the root receives the results. At step 7 the root exits from the loop. At step 8 the worker computes the results, sends them to the root, and exits the loop. This algorithm will not use parallel computing with the particular values .
Users can suppress parallel computing by exchanging values of with .
This may be desirable for achieving good performance. Speedups can be measured by recording the total times for the algorithm to execute a box data type problem for compared to and the root working. These ratios are interesting and a few results are presented in the next section. Algorithm A Define the working list to be the ranks of nodes, using the priority order, that will receive at least one task. The number of nodes on this list is the smaller of the number of tasks and the number of available nodes.