基于延迟敏感应用的边云协同方案

智能设备存在着存储能力以及计算能力不足的问题,导致无法满足计算密集型和延迟敏感型应用的服务质量要求。边缘计算和云计算被认为是解决智能设备局限性的有效方法。为了有效利用边云资源,并在延迟和服务失败概率方面提供良好的服务质量,首先提出了一种三层计算系统框架,然后考虑到边缘服务器的异构性和任务的延迟敏感性,在边缘层提出了一种高效的资源调度策略。三层计算系统框架可以根据应用程序的延迟敏感性提供计算资源和传输时延,保证了边缘资源的有效利用以及任务的实时性。仿真结果验证了所提资源调度策略的有效性,并表明该调度算法优于现有传统方法。     

User allocation-aware edge cloud placement in mobile edge computing

Mobile edge computing is emerging as a novel ubiquitous computing platform to overcome the limit resources of mobile devices and bandwidth bottleneck of the core network in mobile cloud computing. In mobile edge computing, it is a significant issue for cost reduction and QoS improvement to place edge clouds at the edge network as a small data center to serve users. In this paper, we study the edge cloud placement problem, which is to place the edge clouds at the candidate locations and allocate the mobile users to the edge clouds. Specifically, we formulate it as a multiobjective optimization problem with objective to balance the workload between edge clouds and minimize the service communication delay of mobile users. To this end, we propose an approximate approach that adopted the K-means and mixed-integer quadratic programming. Furthermore, we conduct experiments based on Shanghai Telecom's base station data set and compare our approach with other representative approaches. The results show that our approach performs better to some extent in terms of workload balance and communication delay and validate the proposed approach.     

Matrix based proactive resource provisioning in mobile cloud environment

Mobile cloud computing is a dynamic, virtually scalable and network based computing environment where mobile device acts as a thin client and applications run on remote cloud servers. Mobile cloud computing resources required by different users depend on their respective personalized applications. Therefore, efficient resource provisioning in mobile clouds is an important aspect that needs special attention in order to make the mobile cloud computing a highly optimized entity. This paper proposes an adaptive model for efficient resource provisioning in mobile clouds by predicting and storing resource usages in a two dimensional matrix termed as resource provisioning matrix. These resource provisioning matrices are further used by an independent authority to predict future required resources using artificial neural network. Independent authority also checks and verifies resource usage bill computed by cloud service provider using resource provisioning matrices. It provides cost computation reliability for mobile customers in mobile cloud environment. Proposed model is implemented on Hadoop using three different applications. Results indicate that proposed model provides better mobile cloud resources utilization as well as maintains quality of service for mobile customer. Proposed model increases battery life of mobile device and decreases data usage cost for mobile customer.     

Characterizing application scheduling on edge,fog, and cloud computing resources

Cloud computing has grown to become a popular distributed computing service offered by commercial providers. More recently, edge and fog computing resources have emerged on the wide-area network as part of Internet of things (IoT) deployments. These three resource abstraction layers are complementary, and offer distinctive benefits. Scheduling applications on clouds has been an active area of research, with workflow and data flow models offering a flexible abstraction to specify applications for execution. However, the application programming and scheduling models for edge and fog are still maturing, and can benefit from learnings on cloud resources. At the same time, there is also value in using these resources cohesively for application execution. In this article, we offer a taxonomy of concepts essential for specifying and solving the problem of scheduling applications on edge, fog, and cloud computing resources. We first characterize the resource capabilities and limitations of these infrastructure and offer a taxonomy of application models, quality-of-service constraints and goals, and scheduling techniques, based on a literature review. We also tabulate key research prototypes and papers using this taxonomy. This survey benefits developers and researchers on these distributed resources in designing and categorizing their applications, selecting the relevant computing abstraction(s), and developing or selecting the appropriate scheduling algorithm. It also highlights gaps in literature where open problems remain.     

An energy-efficient scheduling scheme for time-constrained tasks in local mobile clouds

Mobile Cloud Computing (MCC) enables mobile devices to use resource providers other than mobile devices themselves to host the execution of mobile applications. Various mobile cloud architectures and scheduling algorithms have been studied recently. However, how to utilize MCC to enable mobile devices to run complex real-time applications while keeping high energy efficiency remains a challenge. In this paper, firstly, we introduce the local mobile clouds formed by nearby mobile devices and give the mathematical models of the mobile devices and their applications. Secondly, we formulate the scheduling problem in local mobile clouds. After describing the resource discovery scheme and the adaptive, probabilistic scheduling algorithm, we finally validate the performance of the proposed algorithm by simulation experiments.     

移动边缘计算环境下的动态资源分配策略

在通讯设备爆炸式增长的时代,移动边缘计算作为5G通讯技术的核心技术之一,对其进行合理的资源分配显得尤为重要。移动边缘计算的思想是把云计算中心下沉到基站部署(边缘云),使云计算中心更加靠近用户,以快速解决计算资源分配问题。但是,相对于大型的云计算中心,边缘云的计算资源有限,传统的虚拟机分配方式不足以灵活应对边缘云的计算资源分配问题。为解决此问题,提出一种根据用户综合需求变化的动态计算资源和频谱分配算法(DRFAA),采用"分治"策略,并将资源模拟成"流体"资源进行分配,以寻求较大的吞吐量和较低的传输时延。实验仿真结果显示,动态计算资源和频谱分配算法可以有效地降低用户与边缘云之间的传输时延,也可以提高边缘云的吞吐量。     

分布式云的研究进展综述

云计算作为全新的计算模式,将数据中心的资源包括计算、存储等基础设施资源通过虚拟化技术以服务的形式交付给用户,使得用户可以通过互联网按需访问云内计算资源来运行应用.为面向用户提供更好的服务,分布式云跨区域联合多个云站点,创建巨大的资源池,同时利用地理分布优势改善服务质量.近年来分布式云的研究逐渐成为学术界和工业界的热点.文中围绕分布式云系统中研究的基本问题,介绍了国际国内的研究现状,包括分布式云系统的架构设计、资源调度与性能优化策略和云安全方案等,并展望分布式云的发展趋势.     

基于极大团的边缘云节点聚合算法

组合多个边缘云可以向用户提供更强大的云计算服务,在大量边缘云节点集合中选择适当的节点进行组合是一项具有挑战性的任务。该问题被建模成由云节点作为顶点、节点之间的链路作为边的资源拓扑图。云组合的构建过程等同于在该图中选择子图的过程,这是一个NP完全问题。子图的选择策略是决定云组合性能的重要因素,现有的minStar算法贪心地选择节点之间通信延迟最小的子图,将最优资源分配给当前用户,导致了局部最优和全局性能不良的问题。鉴于此,提出基于极大团的边缘云资源分配算法,提取图中的极大团并将其划分为若干互不重叠的规模较小的完全子图,以子图为单位构建资源块,以资源块为单位进行资源的分配。实验结果表明,与minStar算法相比,新算法将全局最大通信延迟降至原来的50%。     

Resource provisioning in Science Clouds: Requirements and challenges

Cloud computing has permeated into the information technology industry in the last few years, and it is emerging nowadays in scientific environments. Science user communities are demanding a broad range of computing power to satisfy the needs of high‐performance applications, such as local clusters, high‐performance computing systems, and computing grids. Different workloads are needed from different computational models, and the cloud is already considered as a promising paradigm. The scheduling and allocation of resources is always a challenging matter in any form of computation and clouds are not an exception. Science applications have unique features that differentiate their workloads; hence, their requirements have to be taken into consideration to be fulfilled when building a Science Cloud. This paper will discuss what are the main scheduling and resource allocation challenges for any Infrastructure as a Service provider supporting scientific applications.     

基于Kriging代理模型的动态云任务调度方法

任务调度在云计算环境中发挥着重要作用。提出一种基于Kriging代理模型的动态云任务调度方法。通过对云任务在不同资源组合下的性能表现进行Kriging代理模型建模并优化,从而得到对应于该云任务的最优资源分配方案;利用云平台的API,可动态对该云任务实施资源调度。基于OpenStack开源云平台,对两个工程计算应用进行了任务调度性能测试,结果表明该方法可有效动态调整云任务中的资源配给,按需按优对平台中的云任务进行资源调度。     

基于Wi-Fi与Web的云计算资源调度算法研究

为缩短云计算执行时间,改善云计算性能,在一定程度上加强云计算资源节点完成任务成功率,需要对云计算资源进行调度;当前的云计算资源调度算法在进行调度时,通过选择合适的调度参数并利用CloudSim仿真工具,完成对云计算资源的调度;该算法在运行时无法有效地进行平衡负载,导致云计算资源调度的均衡性能较差,存在云计算资源调度结果误差大的问题;为此,提出一种基于Wi-Fi与Web的云计算资源调度算法;该算法首先利用自适应级联滤波算法对云计算资源数据流进行滤波降噪,然后以降噪结果为基础,采用本体论对云计算资源进行预处理操作,最后通过人工蜂群算法完成对云计算资源的调度;实验结果证明,所提算法可以良好地应用于云计算资源调度中,有效提高了云计算资源利用率,具有实用性以及可实践性,为该领域的后续研究发展提供了可靠支撑。     

边缘环境下计算密集型任务调度研究综述

随着移动设备数量的急剧增长及计算密集型应用如人脸识别、车联网以及虚拟现实等的广泛使用,为了实现满足用户QoS请求的任务和协同资源的最优匹配,使用合理的计算密集型应用的任务调度方案,从而解决边缘云中心时延长、成本高、负载不均衡和资源利用率低等问题。阐述了边缘计算环境下计算密集型应用的任务调度框架、执行过程、应用场景及性能指标。从时间和成本、能耗和资源利用率以及负载均衡和吞吐量为优化目标的边缘计算环境下计算密集型应用的任务调度策略进行了对比和分析,并归纳出目前这些策略的优缺点及适用场景。通过分析5G环境下基于SDN的边缘计算架构,提出了基于SDN环境下的边缘计算密集型数据包任务调度策略、基于深度强化学习的计算密集型应用的任务调度策略和5G IoV网络中多目标跨层任务调度策略。从容错调度、动态微服务调度、人群感知调度以及安全和隐私等几个方面总结和归纳了目前边缘计算环境中任务调度所面临的挑战。     

云计算环境任务调度方法研究综述

随着应用程序计算需求的快速增长,异构计算资源不断地增多,任务调度成为云计算领域中重要的研究问题。任务调度负责将用户任务匹配给合适的虚拟计算资源,算法的优劣将直接影响响应时间、最大完工时间、能耗、成本、资源利用率等一系列与用户和云服务供应商经济利益密切相关的性能指标大小。针对独立任务和科学工作流这两类云环境主流任务,结合不同云环境特征对任务调度算法研究进展进行综述和讨论。回顾梳理已有的任务调度类型、调度机制及其优缺点;归纳单云环境和混合云、多云及联盟云等跨云环境下任务调度特征,并对部分相关典型文献的使用方法、优化目标、优缺点等方面进行阐述,在此基础上讨论各个环境下任务调度研究现状;进一步对各类环境下文献使用的调度优化方法进行梳理,明确其使用范围;总结并指出需要对计算数据密集型应用在跨云环境下的任务调度研究进行重点关注。     

On Cost Aware Cloudlet Placement for Mobile Edge Computing

As accessing computing resources from the remote cloud inherently incurs high end-to-end (E2E) delay for mobile users, cloudlets, which are deployed at the edge of a network, can potentially mitigate this problem. Although some research works focus on allocating workloads among cloudlets, the cloudlet placement aiming to minimize the deployment cost (i.e., consisting of both the cloudlet cost and average E2E delay cost) has not been addressed effectively so far. The locations and number of cloudlets have a crucial impact on both the cloudlet cost in the network and average E2E delay of users. Therefore, in this paper, we propose the Cost Aware cloudlet PlAcement in moBiLe Edge computing (CAPABLE) strategy, where both the cloudlet cost and average E2E delay are considered in the cloudlet placement. To solve this problem, a Lagrangian heuristic algorithm is developed to achieve the suboptimal solution. After cloudlets are placed in the network, we also design a workload allocation scheme to minimize the E2E delay between users and their cloudlets by considering the user mobility. The performance of CAPABLE has been validated by extensive simulations.      

Cloud data analysis using a genetic algorithm‐based job scheduling process

Data analysis plays a major role in different research applications that require a large volume of data. Cloud computing can provide computer processing resources and device‐to‐device data sharing based on user requirements. The main goal of cloud computing is to allow users and enterprise of varying capabilities to store and process data in an efficient way and to access and distribute resources. However, a crucial problem in cloud computing is job scheduling for numerous users. Prior to the implementation of job scheduling, jobs must be categorized according to degree of criticalness, privacy and time required. Based on the experimental results, the combination of tasks was successfully determined by the processor. In heterogeneous multiprocessor systems, customized job scheduling is highly critical for obtaining optimal job performance. In this paper, an evolutionary genetic algorithm was used for obtaining better results in job scheduling, thereby improving performance in the cloud system in this regard. The genetic algorithm‐based job scheduling process introduced minimizes the investment in time through effective allocation of user requests in order to enhance the overall efficiency of the system.     

An energy-efficient task scheduling for mobile devices based on cloud assistant

Mobile cloud computing is an emerging service model to extend the capability and the battery life of mobile devices. Mostly one network application can be decomposed into fine-grained tasks which consist of sequential tasks and parallel tasks. With the assistance of mobile cloud computing, some tasks could be offloaded to the cloud for speeding up executions and saving energy. However, the task offloading results in some additional cost during the communication between cloud and mobile devices. Therefore, this paper proposes an energy-efficient scheduling of tasks, in which the mobile device offloads appropriate tasks to the cloud via a Wi-Fi access point. The scheduling aims to minimize the energy consumption of mobile device for one application under the constraint of total completion time. This task scheduling problem is reconstructed into a constrained shortest path problem and the LARAC method is applied to get the approximate optimal solution. The proposed energy-efficient strategy decreases 81.93% of energy consumption and 25.70% of time at most, compared with the local strategy. Moreover, the applicability and performance of the proposed strategy are verified in different patterns of applications, where the time constraint, the workload ratio between communication and computation are various.     

混合云中的一个高效协调器

云计算提供了4种部署模型:公有云、私有云、社区云和混合云.通常,一个私有云中可用的资源是有限的,因此云用户不得不从公有云租用资源.这意味着云用户将会产生额外的费用.越来越多的企业选择混合云来部署它们的应用.在混合云中,为了实现用户的利益最大化,必须满足使用资源的费用最小化和用户的QoS,为此为混合云用户提供了一个既能最小化资源费用又能保证满足QoS的资源分配方法.实验结果表明,该算法在保持低操作成本的同时还满足了用户的QoS.     

A meta-heuristic optimization approach to the scheduling of bag-of-tasks applications on heterogeneous clouds with multi-level arrivals and critical jobs

As cloud computing evolves, it is becoming more and more apparent that the future of this industry lies in interconnected cloud systems where resources will be provided by multiple “Cloud” providers instead of just one. In this way, the hosts of services that are cloud-based will have access to even larger resource pools while at the same time increasing their scalability and availability by diversifying both their computing resources and the geographical locations where those resources operate from. Furthermore the increased competition between the cloud providers in conjunction with the commoditization of hardware has already led to large decreases in the cost of cloud computing and this trend is bound to continue in the future. Scientific focus in cloud computing is also headed this way with more studies on the efficient allocation of resources and effective distribution of computing tasks between those resources. This study evaluates the use of meta-heuristic optimization algorithms in the scheduling of bag-of-tasks applications in a heterogeneous cloud of clouds. The study of both local and globally arriving jobs has been considered along with the introduction of sporadically arriving critical jobs. Simulation results show that the use of these meta-heuristics can provide significant benefits in costs and performance.     

云计算中基于遗传算法的数据布局策略

数据布局的合理性直接影响数据中心间的数据调度效率,进而提高对用户的数据采集效率。论文以数据中心之间数据调度为基础建立数学模型,利用分布式云计算技术处理用户的海量数据,并提供高性能计算资源和海量存储资源模式。在分布式云计算系统中,数据密集型计算可以有效处理数据中心之间的数据调度,通过遗传算法的全局优化能力产生最佳的近似解,并最终获得数据布局的最佳近似结果。实验结果表明,遗传算法可以有效地计算出最优数据布局的近似结果,并使数据中心之间的数据调度最小化。     

Profit maximization based task scheduling in hybrid clouds using whale optimization technique

ABSTRACT

In cloud computing system, task scheduling plays an important key role. The tasks provided by the user to allocate in cloud have to pay for the share of resources that are used by them. The requirement of task scheduling in the cloud environment has become more and more complex, and the amount of resources and tasks is growing rapidly. Therefore, an efficient task-scheduling algorithm is necessary for allocating the task efficiently in the cloud, which can achieve minimum resource utilization, minimum processing time, high efficiency, and maximum profit. In hybrid clouds to maximize the profit of a private cloud while guaranteeing the service delay bound of delay-tolerant tasks is studied in this article. Here, a new metaheuristic technique inspired from the bubble-net hunting technique of humpback whales, namely whale optimization algorithm (WOA), has been applied to solve the task-scheduling problem. Then WOA algorithm is compared with existing algorithms such as artificial bee colony algorithm (ABC) and Genetic algorithm (GA). The experimental result shows that the proposed WOA algorithm greatly increases the efficiency and achieves maximum profit for the private cloud.