Configuring, Creating, and Destroying a Graph

The graph describes the data transmission relationship between engines in a service. The Matrix framework defines the graph data structure in a protobuf file. You can define the graph configurations in the configuration file.

For details about the graph keywords, see Graph Keywords. For more details, see the Matrix API Reference.

The following provides a simple graph configuration file, which will create a graph service flow with the ID of 1000. The service flow contains three engines. Figure 1 shows the data transmission relationship between the engines.

Figure 1 Data transmission relationship between engines

graphs {
    graph_id: 1000           # A single chip supports multiple graphs, whose IDs must be greater than 0 and must be unique within the chip.
    device_id: "0"           # ID of the chip on which the graph is running
    priority: 1              # priority

    # user-defined engine, which can be instantiated into multiple engines. Multiple engines are differentiated by ID.
    engines {
        id: 2001                                 # engine ID
        engine_name: "ObjectDetectionEngine"     # class name of the user-defined engine
        side: DEVICE                             # whether the engine runs on the host or device
        so_name: "./libObjectDetectionEngine.so" # name and host-side path of the dynamic library, which is copied by the Matrix framework to the device side
        # user-definable parameters
        ai_config{
            items{
                name: "model"                   # model name
                value: "./FaceDetection.om"     # host-side path of the model, which is copied by the Matrix framework to the device side
            }
            items{
                name: "mode"
                value: "test"
            }
        }
    }
    engines {
        id: 1000
        engine_name: "DecodeEngine"
        side: DEVICE
        so_name: "./libDecodeEngine.so"
    }
    engines {
        id: 2002
        engine_name: "PostProcess"
        side: HOST
    }

    # Describes interface connections between engines.
    connects {
        src_engine_id: 1000                     # source engine ID for data transmission 
        src_port_id: 0                          # source port ID for data transmission
        target_engine_id: 2001                  # target engine ID for data transmission
        target_port_id: 0                       # target port ID for data transmission
    }
    connects {
        src_engine_id: 2001
        src_port_id: 0
        target_engine_id: 2002
        target_port_id: 0
    }
}

Table 1 lists three frequently used graph APIs provided by the Matrix. For details, see the Matrix API Reference.