We present constant approximative policies for preemptive stochastic scheduling. We derive policies with a guaranteed performance ratio of 2 for scheduling jobs with release dates on identical parallel machines subject to minimizing the sum of weighted completion times. Our policies as well as their analysis apply also to the recently introduced more general model of stochastic online schedulin...

This research proposes a preemptive fuzzy goal programming model for multi-objective multi-mode resource constrained project scheduling problem. The objectives of the problem are minimization of the total time and the total cost of the project. Objective in a multi-mode resource-constrained project scheduling problem is often a minimization of makespan. However, both time and cost should be con...

The most important requirement for real-time systems is the capability to support the timely execution of applications. Real-time scheduling over a single processor has been widely studied in the last thirty years, and it has been proven that the non-preemptive version of Earliest Deadline First (EDF) algorithm is optimal [1], in the sense that if a set of tasks is schedulable, it is also sched...

Even though real-time systems have the stringent constraint of completing tasks before their deadlines, many existing real-time operating systems do not implement fault tolerance capabilities. In this paper we describe the development and implementation of a non-preemptive fault tolerant real-time policy for aperiodic dynamic tasks. We implemented non-preemptive fault-tolerant scheduling and re...

ABSTRACT: Most of the existing packet-scheduling mechanism of WSN use First Come First Served(FCFS),nonpreemptive priority and preemptive prior it scheduling algorithms. These algorithms incur a high processing overhead and long end-to-end data transmission delay due to improper allocation of data packets to queues in multilevel queue scheduling algorithms. Moreover, these algorithms are not dy...

Modern safety-critical systems, such as avionics, tend to be mixed-critical, because integration of different tasks with different assurance requirements can effectively reduce their costs in terms of hardware, at the risk, however to increase the costs for certification, in particular in the context of proving their schedulability. To simplify the certification costs such systems use Time Trig...

This paper presents a Probabilistic Preemptive (PP) scheduling discipline for service differentiation in Optical Burst Switching (OBS) networks. The main idea of PP is that a probabilistic parameter is added to the preemptive scheduling discipline. With PP, a high priority burst preempts a low priority burst in a probabilistic manner. By changing the probabilistic parameter, PP can achieve flex...

We study graph multicoloring problems, motivated by the scheduling of dependent jobs on multiple machines. In multicoloring problems, vertices have lengths which determine the number of colors they must receive, and the desired coloring can be either contiguous (non-preemptive schedule) or arbitrary (preemptive schedule). We consider both the sum-of-completion times measure, or the sum of the l...

Recent embedded processor architectures containing multiple heterogeneous cores and non-coherent caches, bring renewed attention to the use of Software Transactional Memory (STM) as a building block for developing parallel applications. STM promises to ease concurrent and parallel software development, but relies on the possibility of abort conflicting transactions to maintain data consistency,...

List Scheduling is an approach to finding an approximate non-preemptive schedule on parallel machines, initially due to Graham [4]. We present and analyze the approach for identical machines and an arbitrary jobs list. Then an algorithm based on the LPT (Longest Processing Time) list with an improved performance is discussed, based on [2, 5]. We stress the role of LPT schedules for determining ...