In this research a scenario is assumed where periodic real-time jobs are being run on a heterogeneous cluster of computers, and new aperiodic parallel real-time jobs, modelled by Directed Acyclic Graphs (DAG), arrive at the system dynamically. In the scheduling scheme presented in this paper, a global scheduler situated within the cluster schedules new jobs onto the computers by modelling their...

Scheduling is an enduring process where the existence of real time information frequently forces the review and modification of pre-established schedules. The real world is complex and complexity generally arises from uncertainty. From this prospective the concept of fuzziness is introduced in the field of scheduling. The present paper pertains to a bi-criterion in n-jobs, three machines fl...

In this research, a scenario is assumed where periodic real-time jobs are being run on a heterogeneous cluster of computers, and new aperiodic parallel real-time jobs, modelled by Directed Acyclic Graphs (DAG), arrive at the system dynamically. In the scheduling scheme presented in this paper, a global scheduler situated within the cluster schedules new jobs onto the computers by modelling thei...

This paper presents an algorithm for scheduling jobs in soft real-time systems. To simplify the scheduling for soft real-time systems, we introduce a “two-level deadline” scheme. Each job in the system has two deadlines, which we call first-level and second-level deadlines, respectively. The first-level deadline is the same as the deadline in traditional real-time systems. The second-level dead...

The static and analytic scheduling approach is very difficult to follow and is not always applicable in real-time. Most of the scheduling algorithms are designed to be established in offline environment. However, we are challenged with three characteristics in real cases: First, problem data of jobs are not known in advance. Second, most of the shop’s parameters tend to be stochastic. Third, th...

In this paper, we consider soft real-time systems with redundant off-the-shelf processing components (e.g., CPU, disk, network), and show how applications can exploit the redundancy to improve the system's ability of meeting response time goals (soft deadlines). We consider two scheduling policies, one that evenly distributes load (Balance), and one that partitions load according to job slackne...

We explore the integration of firm real-time processing— where processing completed after its deadline has no value but some jobs may be terminated or skipped—into an integrated real-time system managing hard, soft, and non-realtime processes. We show that it is feasible to add firm realtime processing to an integrated environment and that concurrently executing soft real-time processes can ben...

A dual management of real-time and interactive jobs in dual-core smartphones is presented. The proposed scheme guarantees the end-to-end QoS of real-time applications, while also provides reasonable latency for interactive applications. To this end, high performance NVRAM is adopted as storage of real-time applications, and a dual purpose CPU scheduler, in which one core is exclusively used for...

In this paper, we derive bounds on performance guarantees of online algorithms for real-time preemptive scheduling of jobs with deadlines on K machines when jobs are characterized in terms of their minimum stretch factor α (or, equivalently, their maximum execution rate r = 1/α). We consider two well known preemptive models that are of interest from practical applications: the hard real-time sc...