Value-driven resource assignment in object-oriented real-time dependable systems

The paper deals with object oriented real time dependable systems required to achieve the best usage of the resources, even under adverse circumstances as transient overloads or component failures. Various possible tradeoffs among the different application requirements must be considered to allow a flexible management of system resources. On the basis of a simple formulation of the concept of object value in real time systems we propose a performability metric that represents a suitable measure of system accomplishment level. A planner component is defined which is responsible for implementing a value driven admission policy that maximises the performability index and hence achieves the optimal utilisation of available system resources. The numerical evaluation of a system organisation taken as an example is performed for different load sets and various redundant execution techniques