A resource consumption model is created for a software application, making it possible to predict the resource requirements of the application in different states. The model has a structure corresponding to that of the application itself, and is interpreted to some degree in parallel with the application, but each part of the model is interpreted in less time than it takes to complete the corresponding part of the application, so that resource requirement predictions are available in advance. The model may be interpreted in a look-ahead mode, wherein different possible branches of the model are interpreted so as to obtain resource requirement predictions for the application after completion of the present step. The model may be derived automatically from the application at design or compilation, and populated by measuring the requirements of the application in response to test scenarios in a controlled environment.