The management of performance requirements is a major challenge for information systems as well as other software systems. This is because performance requirements can have a global impact on the target system. In addition, there are interactions and trade-offs among performance requirements, other nonfunctional requirements (NFRs), and the numerous alternatives for the target system. To provide a systematic approach to managing performance requirements, this paper presents a performance requirements framework (PeRF). It integrates and catalogues a variety of kinds of knowledge of information systems and performance. These include: performance concepts, software performance engineering principles for building performance into systems, and information systems development knowledge. In addition, layered structures organize performance knowledge and the development process. All this knowledge is represented using an existing goal-oriented approach, the "NFR framework", which offers a developer-directed graphical treatment for stating NFRs, analyzing and interrelating them, and determining the impact of decisions upon NFRs. This approach allows customized solutions to be built, taking into account the characteristics of the particular domain. The use of PeRF in managing performance requirements is illustrated in a study of performance requirements and other NFRs for a university student record system. This paper concludes with a summary of other studies of information systems, tool support and directions for future work.

Quality characteristics are vital for the success of software systems.To remedy the problems inherent in ad hoc development, a framework has been developed to deal with non-functional requirements (quality requirements or NFRs).Taking the premise that the quality of a product depends on the quality of the process that leads from high-Ievel NFRs to the product, the framework's objectives are to represent NFR-specific requirements, consider design tradeoffs, relate design decisions to IYFRs, justify the decisions, and assist defect detection.The purpose of this paper is to give an initial evaluation of the extent to which the framework's objectives are met.Three small portions of information systems were studied by the authors using the framework.The framework and empirical studies are evaluated herein, both from the viewpoint of domain experts who have reviewed the framework and studies, and ourselves as framework developers and users.The systems studied have a variety of characteristics, reflecting a variety of real application domains, and the studies deal with three important classes of NFRs for systems, namely, accuracy, security, and performance.The studies provide preliminary support for the usefulness of certain aspects of the framework, while raising some open issues.

Non-functional requirements (or quality requirements, NFRs) such as confidentiality, performance and timeliness are often crucial to a software system. Our NFR-framework treats NFRs as goals to be achieved during the process of system development. Throughout the process, goals are decomposed, design tradeoffs are analysed, design decisions are rationalised, and goal achievement is evaluated. This paper shows how a historical record of the treatment of NFRs during the development process can also serve to systematically support evolution of the software system. We treat changes in terms: of (i) adding or modifying NFRs, or changing their importance, and (ii) changes in design decisions or design rationale. This incremental approach is illustrated by a study of changes in banking policies at Barclays Bank.

Performance goals for information systems are treated as a class of nonfunctional requirements (NFRs). A given model for representing NFRs is given to make provisions for: representing a variety of implementation alternatives; expressing performance goals (including responsiveness) in terms of performance and information system concepts; and organizing the process into layers corresponding to subsets of the language to be implemented. The application of the framework is illustrated by mapping the conceptual design of an information system to its implementation, while attempting to meet a set of goals such as 'achieve good time performance for authorizing credit card sales'. A tool is being developed to aid this process.>

A comprehensive framework for representing and using nonfunctional requirements during the development process is proposed. The framework consists of five basic components which provide the representation of nonfunctional requirements in terms of interrelated goals. Such goals can be refined through refinement methods and can be evaluated in order to determine the degree to which a set of nonfunctional requirements is supported by a particular design. Evidence for the power of the framework is provided through the study of accuracy and performance requirements for information systems.>

The features of a compiler for the Taxis design language are described and discussed. Taxis offers an entity-based framework for designing interactive information systems and supports generalisation, classification and aggregation as abstraction mechanisms. Its features include multiple inheritance of attributes, isA hierarchies of transactions, metaclasses, typed attributes, a procedural exception-handling mechanism and an iteration construct based on the abstraction mechanisms supported Developing a compiler for the language involved dealing with the problems of efficiently representing and accessing a large collection of entities, performing (static) type checking and representing isA hierarchies of transactions.