Allreduce method for Dragonfly topology

The invention discloses an Allreduce method for a Dragonfly topology, which comprises the following steps: in each round of recursion, carrying out priority-based topology perception one-to-one matching on nodes participating in communication, exchanging part or all of data between two paired nodes and carrying out reduction, then dividing the nodes into two sets with the same node number according to matching, and carrying out one-to-one matching on the nodes participating in communication; the priority-based topology perception matching step comprises the following sub-steps of: performing first priority matching between nodes on the nodes under the same switch, respectively entering the next round of recursion until only one node is left in the set, and performing second priority matching between the nodes under the same switch; performing third priority matching on partial nodes in different groups; and performing second priority matching on the nodes in the same group. According to the invention, the lin