Performance driven allocation of objects to processor nodes in a distributed system

The authors present a technique for making physical design decisions within a distributed object-oriented system, based on the logical model of system behavior. Starting from the use case model and the object interactions occurring in each use case, an object graph is derived that represents the logical connectivity between the system objects. Weights assigned to edges and nodes represent the cost of object interactions and the cost of the processing carried out by each object, respectively. The paper focuses on the problem of allocating objects to network nodes in order to minimise network traffic. An example is used to illustrate the steps involved. The value of the approach lies in generating performance figures required for physical design decisions directly from the logical design, before data on the performance of the live system is available. It also supports iteration between logical and physical modelling activities. Effective use of the technique requires tool support and functionality for such a tool is described