Abstract. Software systems are today one of the most complex artifacts, they are simultaneously used by hundred-thousand of people sometimes in risk real time operations, such as auctions or electronic commerce. Nevertheless, it is a common practice to deploy them without the expected performance. Software Performance Engineering has emerged as a discipline to complement Software Engineering research in order to address this kind of problems. In this work, we survey some recent contributions in the field of Software Performance Engineering. The approach surveyed has as main features that it uses the UML diagrams to specify the functional and performance requeriments of the system and the stochastic Petri nets formalism to analyse it.