Linux’s real-time performance crucially depends on priority inheritance because—on uniprocessors—it limits the maximum duration of priority inversion to one critical section per lock while ensuring that tasks remain fully preemptable even when holding locks. Unfortunately, priority inheritance is ineffective on multiprocessors under non-global scheduling (i.e., if some tasks may not execute on ...

Preemption threshold scheduling (PTS) provides prominent benefits for fixed priority scheduling such as increased schedulability, reduced context switches, and decreased memory requirements. Since such benefits allow for scalable real-time system design, we have adopted it into our automatic implementation synthesis method for real-time object-oriented models. In this paper, we present the inte...

It is over 40 years since the first seminal work on priority assignment for real-time systems using fixed priority scheduling. Since then, huge progress has been made in the field of real-time scheduling with more complex models and schedulability analysis techniques developed to better represent and analyse real systems. This tutorial style review provides an in-depth assessment of priority as...

Global fixed-priority scheduling of constraineddeadline sporadic tasks systems is important not only for CPU scheduling but also in other domains, for example, scheduling real-time flows in WirelessHART networks designed for industrial process control and monitoring. In this paper, we propose a novel priority assignment scheme for scheduling such task systems on multiprocessors and demonstrate,...

The advent of multiand many-core processors offers enormous performance potential for parallel tasks that exhibit sufficient intra-task thread-level parallelism. With a growth of novel parallel programming models (e.g., OpenMP, MapReduce), scheduling parallel tasks in the real-time context has received an increasing attention in the recent past. While most studies focused on schedulability anal...

We propose a hybrid scheduling algorithm using deferred preemption with an online adjustment. Our approach is to prevent jobs from preempting one another until they have been promoted. We use the tasks’ Worst Case Response Time (WCRT) to determine when a promotion must occur in order to ensure safe execution. During execution, this promotion time is adjusted to extend nonpreemptive execution of...

Real time and non-real-time data packets are the two types of scheduling packets which is used at sensor nodes with resource constraints in WSN of importance to reduce sensors energy and end-to-end delays. Existing First Come First Served, starvation of high priority real-time data packets due to the transmission of a large data packet in nonpreemptive priority scheduling, starvation of nonreal...

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...

For wireless networks operating during emergency conditions, emergency, handoff, and new calls are the main kinds of demand. Different operators will have different policies about which should have higher priority, and how to implement that kind of priority. This paper focuses on applying queuing methods for admission control for the above three types of calls. A Weighted Earliest Deadline sche...

Fixed-task-priority (FTP) scheduling and earliest-deadline-first (EDF) scheduling policies are alike in fixing the priority of each job of a task at the time the job is released. This common feature of FTP and EDF scheduling permits a unified analysis of scheduling failures, to derive new sufficient tests for meeting all deadlines of a set of independent sporadic tasks under a global preemptive...