920,409 research outputs found

    A comparison of classical scheduling approaches in power-constrained block-test scheduling

    Get PDF
    Classical scheduling approaches are applied here to overcome the problem of unequal-length block-test scheduling under power dissipation constraints. List scheduling-like approaches are proposed first as greedy algorithms to tackle the fore mentioned problem. Then, distribution-graph based approaches are described in order to achieve balanced test concurrency and test power dissipation. An extended tree growing technique is also used in combination with these classical approaches in order to improve the test concurrency having assigned power dissipation limits. A comparison between the results of the test scheduling experiments highlights the advantages and disadvantages of applying different classical scheduling algorithms to the power-constrained test scheduling proble

    The Epistemology of scheduling problems

    Get PDF
    Scheduling is a knowledge-intensive task spanning over many activities in day-to-day life. It deals with the temporally-bound assignment of jobs to resources. Although scheduling has been extensively researched in the AI community for the past 30 years, efforts have primarily focused on specific applications, algorithms, or 'scheduling shells' and no comprehensive analysis exists on the nature of scheduling problems, which provides a formal account of what scheduling is, independently of the way scheduling problems can be approached. Research on KBS development by reuse makes use of ontologies, to provide knowledge-level specifications of reusable KBS components. In this paper we describe a task ontology, which formally characterises the nature of scheduling problems, independently of particular application domains and in-dependently of how the problems can be solved. Our results provide a comprehensive, domain-independent and formally specified refer-ence model for scheduling applications. This can be used as the ba-sis for further analyses of the class of scheduling problems and also as a concrete reusable resource to support knowledge acquisition and system development in scheduling applications

    Cloud computing resource scheduling and a survey of its evolutionary approaches

    Get PDF
    A disruptive technology fundamentally transforming the way that computing services are delivered, cloud computing offers information and communication technology users a new dimension of convenience of resources, as services via the Internet. Because cloud provides a finite pool of virtualized on-demand resources, optimally scheduling them has become an essential and rewarding topic, where a trend of using Evolutionary Computation (EC) algorithms is emerging rapidly. Through analyzing the cloud computing architecture, this survey first presents taxonomy at two levels of scheduling cloud resources. It then paints a landscape of the scheduling problem and solutions. According to the taxonomy, a comprehensive survey of state-of-the-art approaches is presented systematically. Looking forward, challenges and potential future research directions are investigated and invited, including real-time scheduling, adaptive dynamic scheduling, large-scale scheduling, multiobjective scheduling, and distributed and parallel scheduling. At the dawn of Industry 4.0, cloud computing scheduling for cyber-physical integration with the presence of big data is also discussed. Research in this area is only in its infancy, but with the rapid fusion of information and data technology, more exciting and agenda-setting topics are likely to emerge on the horizon

    Design citeria for applications with non-manifest loops

    Get PDF
    In the design process of high-throughput applications, design choices concerning the type of processor architecture and appropriate scheduling mechanism, have to be made. Take a reed-solomon decoder as an example, the amount of clock cycles consumed in decoding a code is dependent on the amount of errors within that code. Since this is not known in advance, and the environment in which the code is transmitted can cause a variable amount of errors within that code, a processor architecture which employs a static scheduling scheme, has to assume the worst case amount of clock cycles in order to cope with the worst case situation and provide correct results. On the other hand a processor that employs a dynamic scheduling scheme, can gain wasted clock cycles, by scheduling the exact amount of clock cycles that are needed and not the amount of clock cycles needed for the worst case situation. Since processor architectures that employ dynamic scheduling schemes have more overhead, designers have to make their choice beforehand. In this paper we address the problem of making the correct choice of whether to use a static or dynamic scheduling scheme. The strategy is to determine whether the application possess non-manifest behavior\ud and weigh out this dynamic behavior against static scheduling solutions which were quite common in the past. We provide criteria for choosing the correct scheduling architecture for a high throughput application based upon the environmental and algorithm-specification constraints. Keywords¿ Non-manifest loop scheduling, variable latency functional units, dynamic hardware scheduling, self\ud scheduling hardware units, optimized data-flow machine architecture

    PGGA: A predictable and grouped genetic algorithm for job scheduling

    Get PDF
    This paper presents a predictable and grouped genetic algorithm (PGGA) for job scheduling. The novelty of the PGGA is twofold: (1) a job workload estimation algorithm is designed to estimate a job workload based on its historical execution records, (2) the divisible load theory (DLT) is employed to predict an optimal fitness value by which the PGGA speeds up the convergence process in searching a large scheduling space. Comparison with traditional scheduling methods such as first-come-first-serve (FCFS) and random scheduling, heuristics such as a typical genetic algorithm, Min-Min and Max-Min indicates that the PGGA is more effective and efficient in finding optimal scheduling solutions

    Fast divide-and-conquer algorithms for preemptive scheduling problems with controllable processing times – A polymatroid optimization approach

    Get PDF
    We consider a variety of preemptive scheduling problems with controllable processing times on a single machine and on identical/uniform parallel machines, where the objective is to minimize the total compression cost. In this paper, we propose fast divide-and-conquer algorithms for these scheduling problems. Our approach is based on the observation that each scheduling problem we discuss can be formulated as a polymatroid optimization problem. We develop a novel divide-and-conquer technique for the polymatroid optimization problem and then apply it to each scheduling problem. We show that each scheduling problem can be solved in O(Tfeas(n) log n) time by using our divide-and-conquer technique, where n is the number of jobs and Tfeas(n) denotes the time complexity of the corresponding feasible scheduling problem with n jobs. This approach yields faster algorithms for most of the scheduling problems discussed in this paper

    Reservation-Based Federated Scheduling for Parallel Real-Time Tasks

    Full text link
    This paper considers the scheduling of parallel real-time tasks with arbitrary-deadlines. Each job of a parallel task is described as a directed acyclic graph (DAG). In contrast to prior work in this area, where decomposition-based scheduling algorithms are proposed based on the DAG-structure and inter-task interference is analyzed as self-suspending behavior, this paper generalizes the federated scheduling approach. We propose a reservation-based algorithm, called reservation-based federated scheduling, that dominates federated scheduling. We provide general constraints for the design of such systems and prove that reservation-based federated scheduling has a constant speedup factor with respect to any optimal DAG task scheduler. Furthermore, the presented algorithm can be used in conjunction with any scheduler and scheduling analysis suitable for ordinary arbitrary-deadline sporadic task sets, i.e., without parallelism
    corecore