It is not an overstatement to say that the gap between software design and performance evaluation techniques has caused the misuse of the last ones by software engineers. The UML profile for schedulability, performance and time [13] arose from the intention to close both fields, software engineering and performance analysis. Nevertheless the gap remains, since it is difficult for software engineers to devise which parts of their designs are suitable to represent performance requirements. The profile has started to study this problem from a scenarios viewpoint. In this work, we explore other viewpoints to deal with performance requirements at software design level.