Predicting the behaviour of three-tiered applications: dealing with distributed-object technology and databases

Today’s applications are both object-oriented and based on a new type of three-tiered client–server architecture with clients, processing servers, and data servers as cornerstones. By recognising these trends, industry and researchers have been engaged in defining standards and technologies for communicating the components of Distributed Information Systems and for providing compatible mechanisms to access databases, but a key problem with these complex architectures is still their performance. This paper presents a tool for predicting the performance of systems based on CORBA and DCOM as distributed-object architectures, and OLE-DB and PL/SQL as data-access architectures. The tool is an extension of SMART, a workbench that exploits analytical and simulation performance models to predict the performance of database applications.