Measurement based analysis of temporal behaviour as support for schedulingproblems in parallel and distributed real-time systems

Static analysis, based on scheduling techniques, provides the most typical approach for validation of real-time systems. However, in the case of compl ex real-time systems such as parallel and distributed systems, many simplif ications are made in order to make analysis tractable. This means that even if the system can be statically validated, the real behaviour of the syste m in execution may be different enough from its theoretical behaviour to ma ke it invalid. In these cases, an analysis based on measurement of the syst em in execution constitutes an invaluable aid to the static analysis. This article describes a methodology for the analysis of the temporal behaviour of parallel and distributed realtime systems with end-to-end constraints. T he analysis is based on the measurement of a prototype of the system in exe cution and is supported by a behavioural model. The main components of the model are the sequences of activities throughout the system tasks (transact ions), which are carried out in response to input events, causing the corre sponding output events. Thus, the temporal behaviour of the system is viewe d as a set of real-time transactions competing for the available resources. This article also includes experimental results of applying the methodolog y to the analysis of a well-known case study. (C) 2000 Elsevier Science B.V . All rights reserved.