A distributed computing system is provided. Both a first computing node and a second computing node in the distributed computing system store information about a name, a size, and a communication peer side identifier of a first data flow graph parameter in a data flow graph. The first computing node stores the first data flow graph parameter, where the first computing node and the second computing node generate respective triplets based on same interface parameter generation algorithms and information about the first data flow graph parameter that are stored in the respective nodes. The triplet is used as an interface parameter of a message passing interface (MPI) primitive that is used to transmit the first data flow graph parameter between the first computing node and the second computing node.