Performance Analysis of VM Scheduling Algorithm of CloudSim in Cloud Computing



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IJECT Vo l. 6, Is s u e 1, Sp l-1 Ja n - Ma r c h 2015 ISSN : 2230-7109 (Online) ISSN : 2230-9543 (Print) Performance Analysis Scheduling Algorithm CloudSim in Cloud Computing 1 Md. Ashifuddin Mondal, 2 Sayan Choudhury, 3 Md.Sohel Islam 1 Assistant Pressor, Dept. CSE, Narula Institute Technology, Agarpara, Kolkata, WB, India 2,3 B.Tech Student, Dept. CSE, Narula Institute Technology, Agarpara, Kolkata, WB, India Abstract Cloud Computing is the emerging technology in IT industry which is built on the basis sharing resources over a network. To maximize benefits cloud computing, developers must design mechanisms that optimize the use architectural and deployment models. The users cloud are growing day by day, as a result the number users is increasing and hence it is becoming a serious issue for the developers to schedule the components. Scheduling refers to a set policies to control the order work to be performed by a computer system. Due to the complexity and scale shared resources, it is ten hard to analyze the performance new scheduling and provisioning algorithms on actual Cloud test beds. Therefore, simulation tools are becoming very useful for the evaluation the Cloud computing model which allows researchers to rapidly evaluate the efficiency, performance and reliability their new algorithms on a large heterogeneous Cloud infrastructure. For simulation we need a simulation tool, we are using CloudSim. In this paper we will be analyzing the existing Host allocation policy and allocation policy in terms average waiting time and throughput CloudSim. Keywords Load Balancing, CloudSim,, Data Centre, Broker, Scheduling,. I. Introduction Cloud computing is a distributed computing model that provides users with virtualized, scalable stware and hardware services over the internet, in a pay-as-you-go way. These services are provided according to several fundamental models like IaaS, PaaS, and SaaS. The bottom layer is Infrastructure as a Service (IaaS). It has a service-oriented architecture. It provides access to virtualized computer hardware resources, including machines, network resources, and storage. The most famous service provider is Amazon EC2/S3.The middle layer is Platform as a Service (PaaS), a service platform that developers can use to deploy their own applications. It Provides network access to a programming or runtime environment with data structures embedded in it. Wellknown PaaS service providers include Amazon Web Services and Google App Engine. The top layer is Stware as a Service (SaaS), which enables each user to access services according to his or her requirements. It provides network accessible access to stware application programs. Examples SaaS service providers are Microst s online update service, Trend Micro Internet Security and so on. The importance these services are given in the recent report from Berkeley as: Cloud Computing, the long-held dream computing as a utility has the potential to transform a large part the IT industry, making stware even more attractive as a service [3, 7-6]. Many researchers have been caring out works on the scheduling and allocation the resources in the cloud and they have found that scheduling is a critical problem in Cloud computing. So scheduling is the leading issue in establishing Cloud computing systems. The main goal these scheduling algorithms is to minimize the execution time and cost to achieve the maximum resource utilization. The rest the sections are organized as follows. Section II contains Load Balancing. Section III presents Simulation in cloud computing: CloudSim. Section IV contains scheduling architecture and presents two scheduling policies and its comparison. Section V provides effect different scheduling policies on task execution. Section VI provides the results. Section VII concludes the paper with a summary our future works. II. Load Balancing Load balancing technique is a process in which no node a system remains in idle state while other nodes are over utilized. It plays a big role behind the success the system. Load balancing can work in two ways Co operative way and non Co operative way. In co operative way the nodes work simultaneously in order to optimize the overall response time. In non co operative way the nodes run independently in order to improve the response time local tasks. Load balancing algorithm can be divided into two categories Static load balancing algorithm and Dynamic load balancing algorithm. A static load balancing algorithm does not take into account the previous state or behavior a node while distributing the load while dynamic load balancing algorithm checks the previous state node while distributing the load. Dynamic load balancing is advantageous over static load balancing because if any node fails it will not freeze the entire system. Important objectives load balancing algorithm are cost effectiveness, flexibility and prioritizing resources. Round Robin and First Come First Serve scheduling algorithm falls under static load balancing algorithm. III. Simulation In Cloud Computing CloudSim CloudSim is a framework which allows modeling, simulation and experimenting on designing Cloud computing infrastructure. CloudSim toolkit is developed in the GRIDS laboratory at the University Melbourne. CloudSim facilitates switching between space shared and time shared allocation cores to virtualized services. There are many classes which are the building blocks the CloudSim simulator [4]. Few the main classes are BWProvisioner: This abstract class models the provisioning policy bandwidth to s that are deployed on a Host component. The function this component is to undertake the allocation network bandwidths to set competing s deployed across the data centre. Cloud system developers and researchers can extend this class with their own policies (priority, QoS) to reflect the needs their applications [1]. 1. This class models the Cloud-based application services (content delivery, social networking, business workflow), which are commonly deployed in the data centers. CloudSim represents the complexity an application in terms its computational requirements. Every application component has a pre-assigned www.iject.org International Journal Electronics & Communication Technology 49

IJECT Vo l. 6, Is s u e 1, Sp l- 1 Ja n - Ma r c h 2015 ISSN : 2230-7109 (Online) ISSN : 2230-9543 (Print) instruction length and amount data transfer that needs to be undertaken for successfully hosting the application [2]. 2. Data Centre This class models the core infrastructure level services (hardware, stware) fered by service provider (Amazon, Azure, App Engine) in a Cloud computing environment. It encapsulates a set compute hosts that can be either homogeneous or heterogeneous as regards to their resource configurations (memory, cores, capacity, and storage).furthermore, every DataCenter component instantiates a generalized application provisioning component that implements a set policies for allocating bandwidth, memory, and storage devices [2]. 3. Data Center Broker This class models a broker, which is responsible for mediating between users and service providers depending on users QoS requirements and deploys service tasks across Clouds. The broker acting on behalf users. It identifies suitable Cloud service providers through the Cloud Information Service (CIS) and negotiates with them for an allocation resources that meets QoS needs users. The researchers and system developers must extend this class for conducting experiments with their custom developed application placement policies [3]. 4. Datacenter Characteristics This class extends GridSim sresourcecharacteristics by adding description cost to use datacenter resources. 10. MAl Location This is an abstract class implemented by a Host component that models the policies (space-shared, time-shared) required for allocating processing power to s. The functionalities this class can easily be overridden to accommodate application specific processor sharing policies [4]. 11. Scheduler This abstract class is extended by implementations policies to share processing power among s running in a virtual machine. As described previously, two policies are fered: space-shared (Scheduler) and time-shared (Scheduler) [3]. IV. Scheduling Architecture The objective scheduling is to maximize the resource utilization and minimize processing time the tasks. The scheduler should order the tasks in a way such that quality service is improves and efficiency the tasks are maintained. An efficient task scheduling algorithm must yield less response time and must allow more no. tasks to be submitted by the user. In scheduling architecture user submits the task to the datacentre broker, this broker helps in scheduling the task on virtual machine. In datacentre there are no. hosts, on which no. virtual machines are scheduled and on them tasks are scheduled according to the scheduling policy taken by datacentre broker. 5. Datacenter Tags This class contains tags to be used along with the messages, to identify different message types. 6. Host This class models a physical service in a Cloud-based Data Center. It contains an amount memory and storage, a list processing elements (to represent a multi-core machine), an allocation policy for sharing the processing power among virtual machines, and policies to provisioning memory and bandwidth to the virtual machines. 7. Virtual Machine This class models an instance a, whose management during its life cycle is the responsibility the Host component. Every component has access to a component that stores the characteristics related to a, such as memory, processor, storage, and the s internal provisioning policy, which is extended from the abstract component called Scheduling [4]. 8. Virtual Machine List A helper class to store a bunch virtual machines. It is passed to the DatacenterBroker as the description virtual machines to be instantiated for deployment in the Cloud. 9. Characteristics This class contains the description the virtual machine: memory required, bandwidth, number CPUs, and provisioning policy in use. Different virtual machine templates, like the instances fered by Amazon, are modelled in this class, with the use the related parameters for each fields, like memory, operating system, and number cores [4]. 50 International Journal Electronics & Communication Technology Fig. 1: Scheduling Architecture V. Scheduling scheduling policy is implemented in two levels in CloudSim namely Host level and level. At the host level, it is possible to specify how much the overall processing power each core in a host will be assigned to each. At the level, the Virtual Machines assign specific amount the available processing power to the individual task units that are hosted within its execution engine. In Host level allocation the available s are allotted to the free PE (CPU) or hosts and in level allocation the available cloudlets are allotted to the free s. There are two types policies based on which scheduling is done in CloudSim scheduling policy and scheduling policy. In scheduling policy for Host level one is assigned at a time to a CPU core, when this finishes its task then it schedules another to a CPU core. In scheduling policy for level one task is scheduled at a time www.iject.org

ISSN : 2230-7109 (Online) ISSN : 2230-9543 (Print) to a virtual machine, when this task is completed it schedules another task to the virtual machine. This policy behaves same as the First Come First Serve (FCFS) scheduling algorithm [5], [2], [9], [10]. Algorithm : Step 1: Tasks are arranged in a queue. Step 2: First task is scheduled on the given virtual machine. Step 3: When first task is completed it assigns the next task from the queue. Step 4: If queue is empty it checks for new tasks. Step 5: Then repeat Step 1. Step 6: End. Same algorithm is applicable for both Host level and level scheduling. In scheduling policy for Host level all virtual machines are scheduled on the CPU cores at the same time, it schedules the time among all virtual machines. In scheduling policy for level all tasks are scheduled on the virtual machine at the same time, it schedules the time among all tasks. This policy behaves same as the Round Robin (RR) scheduling algorithm [5], [2], [9], [10]. Algorithm : Step 1: All the tasks are arranged in a queue. Step 2: Then schedule the tasks simultaneously on the virtual machine. Step 3: When queue is empty it checks for new tasks. Step 4: If new task arrives it schedules similarly as in Step 2. Step 5: End. Same algorithm is applicable for both Host level and level scheduling. VI. Effect Different Scheduling Policies on Task Execution IJECT Vo l. 6, Is s u e 1, Sp l-1 Ja n - Ma r c h 2015 :(a) for s and for tasks. (b) for s and for tasks. (c) for s and for tasks. (d) for s and for tasks Here we consider one datacenter with one host with 1 CPU core receiving request for hosting two s and running four tasks units, namely t1, t2, t3, t4. We did not specify which task will run in which, this decision is taken by the scheduling policy. In fig. 2(a), a time-shared scheduling is used for s, and a spaceshared one is used for task units. In this case, each receives a time slice each processing core, and then slices are distributed to task units on space-shared basis. As the core is shared, the amount processing power available to the is comparatively lesser than the other scenarios. As task unit assignment is space-shared, hence only one task can be allocated to each core, while others are queued in for future consideration. In fig. 2(b), a space-shared policy is used for both s and task units, as each contains two cores, only one can run at a given occasion time. Therefore, 2 can only be assigned to the core if 1 finishes the execution task units. The same happens for tasks hosted within the : as each task unit demands only one core. But here 1 takes all the tasks since the tasks are also scheduled via space shared policy. In fig. 2(c), a space shared policy is used for allocating s, but a time-shared policy is used for allocating individual task units within. Hence, during a lifetime, all the tasks assigned to it dynamically context switch until their completion. This allocation policy enables the task units to be scheduled at an earlier time, but significantly affecting the completion time task units that are ahead the queue. In this case as well only 1 gets the chance to execute all the tasks since it is scheduled via space shared policy, as a result 2 does not get a chance to run. In fig. 2(d), a time-shared allocation is applied for both s and task units. Hence, the processing power is concurrently shared by the s and the shares each are concurrently divided among the task units assigned to each. In this case, there are no queues either for virtual machines or for task units. VII. Simulation Result A. Experimental Scenario In this section, we examine the results and approach for both Host level and level allocation policy in terms average waiting time and throughput. CloudSim implements both and scheduling policy. The Host configuration is shown in Table 1. Fig. 2: Effects different Scheduling Policies on task execution Table 1: Host Configuration Table Parameter Values Image size 10000 Memory 512 MB Bandwidth 1000 Data Centre Architecture X86 Data centre OS Linux Data Centre M Xen Data Centre Machines 1 Data Centre Memory per Machines 2048 MB Data Centre storage per Machine 10,000 MB Data Centre available BW per Machines 1000 www.iject.org International Journal Electronics & Communication Technology 51

IJECT Vo l. 6, Is s u e 1, Sp l- 1 Ja n - Ma r c h 2015 ISSN : 2230-7109 (Online) ISSN : 2230-9543 (Print) Data Centre processor per Machines Data Centre policy Service Broker policy 1, 2,,, Table 2: Result Analysis: For Dual Core Core 2 2 12 Average waiting time Throughput 500 125.00 100 166.66 0 250.01 0 250.00 1500 375.00 2500 466.66 0 500.01 0 500.00 Fig. 4: Graph with Respect to Table 3 Fig. 5: Graph With Respect to Table 3 Table 3: Result Analysis: For Single Core Core Average waiting time Throughput 1500 500.1 2500 500.00 0 500.01 0 500.00 3500 1000.01 5500 1000.00 0 1000.01 0 1000.00 Fig. 6: Graph with respect to Table 3 We got the above graphs (Fig. 3, Fig. 4, Fig. 5 and Fig. 6) for a single host having single core processing element receiving request for hosting two s and running several cloudlet s. We did not specify which cloudlet will run in which, this decision is taken by the scheduling policy. The Fig. 5 represents average waiting time cloudlet when policy is space shared and cloudlet allocation policy are space shared and time shared. As host is single core, at a time only one will execute. Hence single execute all the cloudlets either time shared or space shared basis. So here second will not get a chance to run. For time shared cloudlet allocation policy average waiting time is zero. But for space shared cloudlet allocation policy there is some waiting time as it works as a FCFS basis. Fig. 3: Graph With Respect to Table 3 52 International Journal Electronics & Communication Technology The Fig. 6 represents average waiting time cloudlet when policy is time shared and cloudlet allocation policy are space shared and time shared. So two will run concurrently. www.iject.org

ISSN : 2230-7109 (Online) ISSN : 2230-9543 (Print) The Fig. 3 represents throughput cloudlet when policy is space shared and cloudlet allocation policy are space shared and time shared. Hence only one will run in the host and other will not get a chance as the first allocated execute all the cloudlet. The Fig. 4 represents throughput cloudlet when policy is time shared and cloudlet allocation policy are space shared and time shared. So two will run concurrently. IJECT Vo l. 6, Is s u e 1, Sp l-1 Ja n - Ma r c h 2015 [9] IsamAzawiMohialdeen, A Comparative Study Scheduling Algorithms in Cloud Computing Environment, 2013 Science Publications. [10] Ashish Kumar Singh, Sandeep Sahu, MangalNath Tiwari, R. K. Katare,"Scheduling Algorithm with Load Balancing in Cloud Computing, IJCA, pp. 48-43, 2011. VIII. Conclusion and Future Work This paper analyzes that space shared scheduling policy for shows better results as compared to -shared scheduling policy in terms throughput in case single core when cloudlet size is small. But Avg. waiting time is low for time shared allocation. This can be verified from the fact that the throughput in space shared allocation policy is more than the throughput time shared allocation policy both in case single core and dual core. In time shared cloudlet allocation policy, the Avg. waiting time for cloudlet is zero. In further we will try to device efficient scheduling policy for better results in terms waiting time and throughput cloudlet. References [1] Rodrigo N. Calheiros, Rajiv Ranjan, César A. F. De Rose, RajkumarBuyya, CloudSim: A Novel Framework for Modeling and Simulation Cloud Computing Infrastructures and Services. [2] Raj Kumar Buyya, Rajiv Ranjan, Rodrigo N. Calheiros, "Modeling and Simulation Scalable Cloud Computing Environments and the CloudSim Toolkit: Challenges and Opportunities. [3] Rodrigo N. Calheiros, Rajiv Ranjan, Anton Beloglazov, C esar A. F. De Roseand Raj Kumar Buyya,"CloudSim: A toolkit for modeling and simulation cloud computing environments and evaluation resourceprovisioning algorithms, SOFTWARE PRACTICE AND EXPERIENCEStw. Pract.Exper.2011; 41: 23 50, 2010. In Wiley Online Library (wileyonlinelibrary.com). [4] Rodrigo N. Calheiros, Rajiv Ranjan, Anton Beloglazov, César A. F. De Rose, RajkumarBuyya,"CloudSim: A Toolkit for the Modeling and Simulation Cloud ResourceManagement and Application Provisioning Techniques, Stware: Practice and Experience, 41(1), pp. 23-50, Wiley, January 2011. [5] Himani, Harmanbir Singh Sidhu,"Comparative Analysis Scheduling Algorithms Cloudsim in Cloud Computing, International Journal Computer Applications, Vol. 97, 16, July 2014. [6] Soumya Ray, Ajanta De Sarkar, Execution Analysis Load Balancing Algorithms In Cloud Computing Environment, International Journal on Cloud Computing: Services and Architecture (IJCCSA),Vol. 2, 5, October 2012. [7] M. Armbrust, A. Fox, R. Griffith, A. Joseph, R. Katz, A. Konwinski, G. Lee, D. Patterson, A. Rabkin, I. Stoica, M. Zaharia. Above the Clouds: A Berkeley View Cloud computing, Technical Report UCB/EECS-2009-28, University California at Berkley, USA, Feb. 10, 2009. [8] R. Ranjan, R. Buyya, Decentralized Overlay for Federation Enterprise Clouds. Handbook Research on Scalable Computing Technologies, K. Li et. al. (ed), IGI Global, USA, 2009. www.iject.org International Journal Electronics & Communication Technology 53