Methods and systems are provided for modeling a multiprocessor system in a graphical modeling environment. The multiprocessor system may include multiple processing units that carry out one or more processes, such as programs and sets of instructions. Each of the processing units may be represented as a node at the top level of the model for the multiprocessor system. The nodes representing the processing units of the multiprocessor system may be interconnected to each other via a communication channel. The nodes may include at least one read element for reading data from the communication channel into the nodes. The node may also include at least one write element for writing data from the nodes into the communication channel. Each of the processing unit can communicate with other processing unit via the communication channel using the read and write elements. Code may be generated to simulate each node and communication channel in the modeled multiprocessor system. The generated code may then be executed to simulate the model. Based on the results of the simulation, one or more processes may be automatically reassigned to nodes within the model to optimize the performance of the model.