It has long been recognised that standard process algebra has difficulty dealing with actions of different priority, such as for instance an interrupt action of high priority. Various solutions have been proposed. We introduce a new approach, involving the addition of “priority guards” to Milner’s process calculus CCS. In our approach, priority is unstratified, meaning that actions are not assi...

It has long been recognised that standard process algebra has difficulty dealing with actions of different priority, such as for instance an interrupt action of high priority. Various solutions have been proposed. We introduce a new approach, involving the addition of “priority guards” to Milner’s process calculus CCS. In our approach, priority is unstratified, meaning that actions are not assi...

Adding priorities to CCS is di cult, and involves two-stage operational semantics or other complications. By contrast, priorities can be added very simply to a calculus of broadcasting systems (CBS). The reason is the input/output distinction made in CBS, with output actions being autonomous. Priority makes sense only for autonomous actions. As in unprioritised CBS, both strong and weak bisimul...

This paper considers the problem of fixed priority scheduling of periodic tasks where each task’s execution priority may vary. Periodic tasks are decomposed into serially executed subtasks. where each subtask is characterized by an execution time and a fixed priority, and is permitted to have a deadline. A method for determining the schedulability of each task is presented along with its theore...

In this paper, we consider several discrete-time priority queues with priority jumps. In a priority scheduling scheme with priority jumps, real-time and non-real-time packets arrive in separate queues, i.e., the highand low-priority queue respectively. In order to deal with possibly excessive delays however, non-real-time packets in the low-priority queue can in the course of time jump to the h...

We study the problem of priority inversion in distributed real-time and embedded systems and propose a solution based on a distributed version of the priority inheritance protocol (PIP). Previous approaches to priority inversions in distributed systems use variations of the priority ceiling protocol (PCP), originally designed for centralized systems as a modification of PIP that also prevents d...

Priority queues have a great importance in the study of computer communication networks in which different types of traffic require different quality of service standards. The discrete-time non-preemptive priority queuing model with priority jumps is proposed in this paper. On the basis of probability generating functions mean system contents and mean queuing delay characteristics are obtained....

Priority is an important concept in Business Process Management (BPM), useful the context of workflow patterns such as, e.g., cancelable and compensable tasks within business transactions. Unfortunately, presence priority workflows makes them difficult to be analyzed formally by automated validation verification tools. In past, we demonstrated that Reo coordination language can successfully use...