1,470 research outputs found

    A cooperative approach for distributed task execution in autonomic clouds

    Get PDF
    Virtualization and distributed computing are two key pillars that guarantee scalability of applications deployed in the Cloud. In Autonomous Cooperative Cloud-based Platforms, autonomous computing nodes cooperate to offer a PaaS Cloud for the deployment of user applications. Each node must allocate the necessary resources for customer applications to be executed with certain QoS guarantees. If the QoS of an application cannot be guaranteed a node has mainly two options: to allocate more resources (if it is possible) or to rely on the collaboration of other nodes. Making a decision is not trivial since it involves many factors (e.g. the cost of setting up virtual machines, migrating applications, discovering collaborators). In this paper we present a model of such scenarios and experimental results validating the convenience of cooperative strategies over selfish ones, where nodes do not help each other. We describe the architecture of the platform of autonomous clouds and the main features of the model, which has been implemented and evaluated in the DEUS discrete-event simulator. From the experimental evaluation, based on workload data from the Google Cloud Backend, we can conclude that (modulo our assumptions and simplifications) the performance of a volunteer cloud can be compared to that of a Google Cluster

    Allocation of Virtual Machines in Cloud Data Centers - A Survey of Problem Models and Optimization Algorithms

    Get PDF
    Data centers in public, private, and hybrid cloud settings make it possible to provision virtual machines (VMs) with unprecedented flexibility. However, purchasing, operating, and maintaining the underlying physical resources incurs significant monetary costs and also environmental impact. Therefore, cloud providers must optimize the usage of physical resources by a careful allocation of VMs to hosts, continuously balancing between the conflicting requirements on performance and operational costs. In recent years, several algorithms have been proposed for this important optimization problem. Unfortunately, the proposed approaches are hardly comparable because of subtle differences in the used problem models. This paper surveys the used problem formulations and optimization algorithms, highlighting their strengths and limitations, also pointing out the areas that need further research in the future

    Analysis and Development of Efficient Task Scheduling Strategies in Heterogeneous Cloud Environment

    Get PDF
    In recent years, Cloud computing has become the integral part of information technology. Lots of research is being done from academic level to industry level. Cloud computing provides service to the users through internet and other distributed network environment on pay as you use basis and user demand basis. It provides an virtual environment of computing resources which can be utilized by cloud users and cloud applications. Scheduling in cloud systems is one of the biggest challenge. An efficient task scheduler is that which is flexible according to the changing environment of clouds and complexity of the submitted tasks. Efficient use of system and getting highest performance of the system is the primary goal of any task scheduling algorithm. Cloud service providers always struggles with problems such as load balancing, Task completion time and wastage of resources. This thesis basically focuses on Task completion time of tasks submitted to the virtual Machines (VMs). Multiple experiments has been performed in CloudSim 3.0.3 simulation toolkit. All the experimental results have been obtained from CloudSim by using base classes and libraries provided in toolkit. Without using any single physical machine CloudSim library gives an full environment for development and research the different techniques for simulation and modelling. Few most generic task scheduling strategies have been studied for this thesis. Based on the study a new strategy has been proposed. This new strategy is named as SCHFMC algorithm, it’s description and study has been provided in chapter 4. SCHFMC algorithm helps in allocating the tasks to the virtual machines (VMs) with varying processing capacity. It has an efficient way to utilise the full processing power of machine so that system can be active and alive without any failure. This algorithm reduces the total completion time of all tasks submitted to the virtual machines. This algorithm has performed better than generic task scheduling meth
    corecore