International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com A Study on Energy Efficiency and Cost Efficiency in Cloud Computing: A Survey P.Manivel pandian1 ,PG Scholar, Department of CSE, PSNA college of Engineering and Technology, Dindigul - 624619, India. Abstract: Cloud computing is on demand provisioning of virtual resources aggregated together so that by specific contracts users can lease access to their combined power. Cloud computing is a new service model for sharing pool of computing resources that can be rapidly accessed based on converged infrastructure. Cloud allows benefits in terms of elasticity, maintenance cost, and economics of scale and virtualization flexibility. The issues arise in the area of cloud computing are cost optimization, energy consumption, Issues in privacy. If the energy consumption is reduced, cost will also get reduced .In order to address this issue, a survey on energy consumption and cost optimization is done. I.INTRODUCTION Cloud computing is defined as a type of computing that relies on sharing computing resources rather than having local servers or personal devices to handle applications. Cloud computing is comparable to grid computing, a type of computing where unused processing cycles of all computers in a network are harnesses to solve problems too intensive for any stand-alone machine. Data centers are becoming increasingly popular for the pro-visioning of computing resources. The cost and operational expenses of data centers have skyrocketed with the increase in computing capacity. The need for energy consumption can be explained by [1] following facts A typical 5,000 Ft2 data center demands 1.127 MW electrical power. In 2013, data centers in the US consumed approximately 91 billion KWH of electricity, equivalent to the annual output of 34 large (500 MW) coal-fired power plants. Data center electricity [2] consumption is projected to increase to roughly 140 billion KWH annually by 2020; A.Sathya Sofia2, AP, Department of CSE, PSNA college of Engineering and Technology, Dindigul - 624619, India. equivalent to the annual output of 50 power plants, costing American businesses 13 billion US dollars annually in electricity bills, and emitting nearly 100million metric tons of carbon pollution per year Electricity consumption cost has become an increasingly significant fraction of the total cost of ownership of current and future data centers. Another fact is that servers are only busy 10-30 percent of the time on average. As cloud computing is predicted to grow, substantial power consumption will result in not only huge operational cost but also tremendous amount of car-bon dioxide (CO2) emissions. Therefore energy and cost efficiency in cloud computing has become a vital on. II. CLOUD COMPUTING AND ITS SERVICES Cloud computing is on-demand Provisioning of virtual resources aggregated together so that by specific contracts users can lease access to their combined power. The cloud allows benefits in terms of elasticity, maintenance costs, and economics of scale and virtualization flexibility. Furthermore, many studies have been affected to find the nature of the HPC applications suitable to be executed on cloud platforms. These services are classified into three main services delivery models: infrastructure as service (IaaS), Platform as service (PaaS) and software as services (Saas). IaaS refers to the practice of delivering on demand IT infrastructure as a commodity to customers. PaaS provides a development platform in which customers can create and execute their own applications. SaaS endows the 55 International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com user with an Integrated Service Comprising hardware, development platforms and applications. Typically, a cloud service provider signs contracts with his customers in the form of service-level agreements (SLAs), which can concern many aspects of cloud computing service. The contract defines the agreed upon service fees for the total virtual resources negotiated by the client as well as the associated service credit if the provider fails to deliver the level of service. III. NEED FOR ENERGY CONSUMPTION that the Data centers are becoming increasingly popular for the pro-visioning of computing resources. The cost and operational expenses of data centers have skyrocketed with the increase in computing capacity. There occurs a condition for consumption of energy in cloud especially in data centers . IV. SURVEY REGARDING ENERGY EFFICIENCY A. Algorithms For Cost- And Deadline-Constrained Provisioning For Scientific Workflow Ensembles In Iaas Clouds [3] IaaS clouds are characterized by on-demand resource provisioning capabilities and a pay-per-use model. A new problem concerning the efficient management of such ensembles under budget and deadline constraints on Infrastructure as a Service (IaaS) is discussed. To solve this problem assess novel algorithms based on static and dynamic strategies for both task scheduling and resource provisioning is developed. The evaluation is done via simulation using a set of scientific workflow ensembles with a broad range of budget and deadline parameters, taking into account such as provisioning delays, and failures, uncertainties in task runtime estimations, task granularity. The most important factor of this algorithm is that determining the performance of an algorithm by its ability to decide which workflows in an ensemble to admit or reject for execution. An example of the application that uses scientific workflow is Cyber Shake Each workflow in a Cyber Shake ensemble generates a hazard curve for a particular geographic location, and several hazard curves are combined to create a hazard map. In a 2013 study, Cyber Shake was used to generate a set of hazard maps over 286 sites that required an ensemble of 288workflows.Problem of scheduling and resource provisioning for scientific workflow ensembles on IaaS clouds is addressed in this paper .The goal of this work is to maximize the number of user-prioritized workflows that can be completed given budget and deadline constraints. We developed three algorithms to solve this problem: two dynamic algorithms, DPDS and WA-DPDS, and one static algorithm, SPSS. The algorithms were evaluated via simulation on ensembles of synthetic workflows, which were generated based on statistics from real scientific applications. Results show that an admission procedure based on workflow structure and estimates of task runtimes can significantly improve the quality of solutions. B. Cost-Aware Challenges For Workflow Scheduling Approaches In Cloud Computing Environments: Taxonomy And Opportunities [4] The main objective of this paper is to facilitate researchers in selecting appropriate cost-aware (WFS) approaches from the available pool of alternatives. To achieve this objective, we conducted an extensive review to investigate and analyze the underlying concepts of the relevant approaches. The cost-aware relevant challenges of WFS in cloud computing are classified based on Quality of Service (QoS) performance, system functionality and system architecture, which ultimately result in a taxonomy set. Workflow Scheduling (WFS) mainly focuses on task allocation to achieve the desired workload balancing by pursuing optimal utilization of available resources. to solve specific WFS problems in cloud computing by providing different services to cloud users on pay-as-you-go and on-demand basis the challenges affecting WFS execution cost have been discussed prior work did not consider such challenges collectively. main benefits of migrating workflow to cloud computing are (i) enable the utilization of various cloud services to facilitate the automation of distributed large-scale work flow execution;(ii) significant reduction of hardware expenditure for 56 International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com work flow execution by sharing and providing resources in cloud systems; and (iii) increased user satisfaction along with reduced execution cost and time by obtaining the pay as you-go business model. WFS provide the ability to get access to other cloud ser-vices and facilitate the Service Level Agreements (SLA). For cost-aware Workflow Scheduling (WFS) challenges. Firstly, it presents the sub-taxonomy of cost-aware challenges. Then, it depicts the correlation of these challenges with key aspects of cloud workflow system. Finally, it provides grouping of reviewed approaches based on the profitability by extracting their association with cost-aware challenges. Cost-aware Workflow Scheduling (WFS) remained an active area of research since emergence of cloud and grid computing for workflow applications. Cost-aware WFS challenges such system functionality, and system architecture. To classify the current state-of-the-art cost-aware WFS approaches, we devised three tax-anomies covering various aspects of WFS including cost-aware challenges, cloud workflow system, and cost-aware profitability. Consideration of aforementioned aspects can further improve the robustness and flexibility of WFS approaches to design a costeffective solution. Furthermore multi-criteria based cost optimization can help in providing optimal (WFS) solutions and hence the presented work can be helpful in improving the body of evidence in the field of (WFS). The findings of this review provide a roadmap for developing cost-aware models which will motivate researchers to propose better costaware approaches for service consumers and/or utility providers in cloud computing. C.Optimizing Energy Consumption With Task Consolidation In Clouds [5] To make best use of utilization of cloud computing resources one of the best ways is Task consolidation. Maximize source exploitation provides various benifits such as the rationalization of maintenance IT service customization, and (QoS) and reliable services However Maximize source exploitation does not mean efficient energy use. Much of the creative writing shows that energy consumption and resource exploitation in clouds are highly united. Some of the creative writing aims to decrease resource exploitation in order to save energy, while others try to reach a balance between resource exploitation and energy consumption. In order to solve this problem a best technique energyaware task consolidation (ETC) technique that minimizes energy consumption. ETC achieves this by restricting CPU use below a species peak threshold. The proposed technique solves this problem by consolidating tasks amongst virtual clusters. In addition, the energy cost model considers network latency when a task migrates to another virtual cluster. To evaluate the performance of ETC we compare it against Max Utilization (Max Util). a recently urbanized greedy algorithm that aims to maximize cloud computing resources is the (Max Util). Energy consumption varies according to CPU utilization. Higher CPU utilization usually implies greater energy consumption. However, higher CPU utilization does not equate to energy efficiency. The task consolidation strategy uses the best-fit strategy to optimize resource utilization The best strategy achieves this by migrating tasks to whichever VM will most closely approach the target CPU utilization threshold. The CPU utilization threshold depends on hardware architecture and may differ on different cloud systems. Considering the architecture (ETC) of most cloud systems, a default CPU utilization threshold of 70% is used to demonstrate task consolidation management amongst virtual clusters. Idle state of virtual machines and network transmission are assumed to be a constant ratio of basic energy consumption these values can be adjusted on different cloud systems in order to get better performance from the (ETC) method. ETC is designed to work in a data center for VC and VMs that reside on the same rack or on racks where network band-width is relatively constant. The simulation results show that ETC can significantly reduce power consumption when managing task consolidation for cloud systems. ETC has up to 17% improvement over a recent work that reduces energy consumption by maximizing resource utilization. D. Analyzing Hadoop Power Consumption And Impact On Application Qos [6] 57 International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com One of the key reasons for migrating to Cloud environments is often identified as Energy efficiency. It is assured that a data center in the surroundings of the Cloud to achieve greater energy efficiency at a reduced cost compared to a local operation. In this effort we inspect and measure energy consumption of a number of virtual machines running the Hadoop system. Our idea is to understand the tradeoffs between energy efficiency and performance for such a workload. From our results we generalize and speculate on how such an analysis could be used as a basis to establish a Service Level Agreement (SLA) with a Cloud provider in particular where there is likely to be a high level of inconsistency both in performance and energy use. The quality of services (QoS) related metrics especially latency are one of the most challenging to support. This effort provides some effort to find close relationship between power consumption and QoS related metrics, describing how a combined consideration of these two metrics could be supported for a particular workload. It is also useful to note that the business case for migrating to Cloud computing systems has often cantered on the cost savings that would arise due to reduced use of energy at a client site It is often stated that due to the economies of scale, the ability to negotiate cheaper energy tariffs and the use of renewable energy sources, data centre operators are able to offer both cost and energy efficient operational systems. The purpose of this work has been to measure and distinguish power consumption for high throughput workloads by means of Hadoop. Such dimension can be used as the basis for developing a workload power utilization model for analyzing social media data. The main conclusion is that there is a non-linear relationship between the number of virtual machines, the workloads that these VMs execute and the power utilization seen on the physical machine. Identifying how many VMs are needed to achieve a particular throughput at a given power usage profile can be undertaken based on the results reported in this work. Variability such as (such as, sudden drops or peaks is power usage that cannot be easily explained) in power consumption over multiple runs of the same workload is also considered. This work provides some insight on the relationship between power consumption and QoS related metrics, describing how a combined consideration of these two metrics could be supported for a particular workload. Our experiments describe when it is desirable to increase the number of resources allocated to a particular application, and when such allocation is unlikely to lead to any significant performance improvement, but still lead to high power usage. By applying the power characterization described in this work to handle Cloud computing environments in an optimized way in terms of power saving and/or performance. E. Energy Efficient Scheduling Of Virtual Machines In Cloud With Deadline Constraint [7] Now a day’s Virtualization is widely used in cloud computing and extremely large amount of electricity is consumed to maintain these virtual machines. As a result the profit of the service providers gets reduced and also harms the environment. If the physical machines(PMs) are heterogeneous the existing energy efficient scheduling methods of virtual machines (VMs) in cloud cannot work well and typically do not use the energy saving technologies of hardware, such as dynamic voltage and frequency scaling (DVFS).In order to avoid these hazards we propose a energy efficient scheduling algorithm(EEVS) of VMs in cloud . A work of fiction conclusion is conducted that there exists best possible frequency for a (PM) to process certain (VM) based on which the notion of optimal performance power relation is defined to weight the homogeneous PMs. The Physical machines with higher optimal performance–power ratio will be assigned to VMs first to save energy. each of the cloud (VM) are allocated to proper (PM) and each active core operates on the most favorable frequency After specific time period the cloud should be reconfigured to consolidate the computation resources to further reduce the power consumption . Virtualization is an important technology typically adopted in cloud to consolidate the resources and support the pay-as-you-go service paradigm. the main challenges for energy efficient scheduling of VMs in cloud computing such as heterogeneity of the PMs, the total power consumption of each PM and the adoption of some energy saving technologies for 58 International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com hardware such as DVFS are overcome by EEVS, an energy efficient scheduling algorithm of virtual machines to reduce the total energy consumed by the cloud, which also supports DVFS well. EEVS consumes less energy and processes more (VM) successfully than the existing methods in most cases, there are still some shortcomings. (PM) and workload are simulated though some information are checked. The simulation results show that our proposed scheduling algorithm achieves over 20% reduction of energy and 8% increase of processing capacity in the best cases. F. Data Center Energy-Efficient Network-Aware Scheduling [8] Data centers are becoming increasingly popular for the pro-visioning of computing resources. The cost and operational expenses of data centers have skyrocketed with the increase in computing capacity, As a fact Energy consumption is a growing concern for data centers operators It is becoming one of the main entries on a data center operational expenses (OPEX) bill. The existing work states that in data centers energy optimization is focusing only on job distribution between computing servers based on workload or thermal profiles. So in this work (DENS) an approach that combines energy efficiency and network awareness which under-lines the role of communication fabric in data center energy consumption was introduced. Data center energy efficient network-aware scheduling (DENS) works by balancing the energy consumption of a data center, individual job performance, and traffic demands. Optimization of the trade-off between job consolidation (to minimize the amount of computing servers) and distribution of traffic patterns (to avoid hotspots in the data center network) is done by the DENS. Implementation and testing of DENS methodology in realistic setups using test beds. (DENS) methodology is particularly relevant in data centers running data-intensive jobs which require low computational load, but produce heavy data streams directed to the end-users. The DENS operation details and its ability to maintain the required level of QoS for the end-user at the expense of the minor increase in energy consumption is shown by the simulation results obtained for three-tier data center architecture. G.Towards High Available And Energy Efficient Virtual Computing Environments In Cloud [9] The construction of flexible and elastic computing environments are enabled by cloud infrastructures which is Empowered by virtualization skill provides an opportunity for energy and resource cost optimization by means of enhancing system availability and achieving high performance. The basic requirement for effective consolidation is the ability to efficiently utilize system resources for highavailability computing and power-efficiency optimization to reduce operational costs and carbon footprints in the environment. Algorithms(POFAME)and (POFARE) are proposed in this work to readjust and to dynamically construct virtual clusters to enable the execution of users’ jobs .To detect and mitigate energy inefficiencies, our decision-making algorithms influence virtualisation tools to provide proactive fault-tolerance and energyefficiency to virtual clusters with an energy optimizing mechanism simulations are conducted by injecting random synthetic jobs and jobs using the latest version of the Google cloud trace logs. The results indicate that our strategy improves the work per Joule ratio by approximately 12.9% and the working efficiency by almost 15.9% compared with other state-of-the-art algorithms. The objective is to maximize the useful work performed by the consumed energy in cases where the infrastructure nodes are subject to failure. Two dynamic VM allocation algorithms, POFAME and POFARE, which use two different methods to provide energyefficient virtual clusters to execute tasks within their deadlines, are used to achieve this objective. POFAME algorithm tries to reserve the maximum required resources to execute tasks, POFARE leverages the cap parameter from the Xen credit scheduler to execute tasks with the minimum required re-sources.the simulation results shows that The improvement in energy efficiency of POFARE over OBFIT is 23.6%, 16.9%,and 72.4% for the average task length ratios of 0.01, 0.1, and 1, respectively and The improvement in working 59 International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com efficiency of POFARE over OBFIT is 26.2%, 20.3%, and 219.7% for the ratios of 0.01, 0.1, and1, respectively . Another relevant problem consists of processing workflows in the cloud, such that jobs where tasks may have precedence also considered. H. Energy - Efficient Deadline Scheduling For Hetero Geneous Systems [10] Power aware scheduling algorithms with deadline constraints for heterogeneous systems is proposed in this paper by formulating the problem of extending the traditional multiprocessor scheduling and design approximation algorithms with analysis on the worst-case performance a pricing scheme for tasks in the way that the price of a task varies as its energy usage as well as largely depending on the tightness of its deadline is also presented The extended online algorithm also outperforms the EDF (Earliest Deadline First)-based algorithm with an average up to 26% of energy saving and 22% of deadline satisfaction. Both the static and online Energy-Efficient Scheduling (EES) algorithm for independent tasks with deadline constraints in heterogeneous systems unit cost metric is introduced. EES algorithm has almost as good energy minimization and deadline satisfaction ability as the optimal solution while the online EES algorithm has a much better performance than the EDF algorithm by the experimental results both user and provider can try to control their own parameters to maximize the respective interests, which has good mercerization application. The proposed algorithm achieves near-optimal energy efficiency, on average 16.4%better for synthetic workload and 12.9% better for realistic workload than the EDD (Earliest Due Date)-based algorithm. It is experimentally shown as well that the pricing scheme provides a flexible tradeoff between deadline tightness and price. V. portions of Energy wastage in idle time. The growing crisis in power shortages has brought up the need for optimizing energy and cost. REFERENCES [1] Author: Keqinli , “Improving Multi core Server Performance and Reducing Energy Consumption by Workload Dependent Dynamic Power Management” (IEEETRANSACTIONS ON CLOUD COMPUTING, VOL.2, April 2015). [2] Author: Ivanoe De Falco, Umberto Scafuri, Ernesto Tarantino, “Mapping of time-consuming multitask applications on a cloud system by multi objective Differential Evolution” (IEEE TRANSACTIONS ON CLOUD COMPUTING, VOL. 4, NO. 2, April 2015). [3] Author: Maciej Malawski Gideon Juve Ewa Deelmanb Jarek Nabrzyski, “Algorithms for costand deadline-constrained provisioning for scientific workflow ensembles in IaaS clouds” (IEEE TRANSACTIONS ON CLOUD COMPUTING, VOL. 3, NO. 2, October 2014). [4] Author: Ehab Nabiel Alkhanak, Sai Peck Lee, Saif Ur Rehman Khan, “Cost-aware challenges for workflow scheduling approaches in cloud computing environments: Taxonomy and opportunities” Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur, Malaysia(Article history Received 25 May 2014 Received in revised form 10 December 2014Accepted 19 January 2015 Available online 2 February 2015). [5] Authors: Ching-Hsien Hsu, Kenn D. Slagter, Shih-Chang Chen , “Optimizing energy consumption with task consolidation in clouds” (Article published on December 2012) CONCLUSION This survey paper underlines the need for energy and cost optimization in cloud especially in datacenters and cloud servers The Energy consumption of different types of cloud servers was investigated and it was shown that there are great [6] Authors: Javier Conejero, Omer Rana, Peter Burnap, Jeffrey Morgan., “Analyzing Hadoop power consumption and impact on application QoS” Article published on journal homepage: www.elsevier.com/locate/fgcs 9 March 2015). 60 International Research Journal of Emerging Trends in Multidisciplinary ISSN 2395 - 4434 Volume 1, Issue 8 October 2015 www.irjetm.com [7] Constraint Author: Youwei Ding, Xiaolin Qin, Liang Liu, “Energy efficient scheduling of virtual machines in cloud with deadline”. Journal homepage: www.elsevier.com/locate/fgcs 11 February 2015) [8] Author: Dzmitry Kliazovich, Pascal Bouvry, Samee Ullah Khan, “Data center energy-efficient network-aware scheduling”. (Published on Cluster Comput DOI 10.1007/s10586-011-0177-4 April 2011) [9] AUTHOR: Altino M. Sampaio, Jorge G, Barbosa, “Towards high-available and energy-efficientvirtual computing environments in the cloud” (Article published on 7 July 2014). [10] Author: Luna Mingyi Zhang, Keqin Li, Yanqing Zhang, “Article: Energy-efficient task scheduling algorithms on heterogeneous computers with continuous and discrete speeds” (published on 28 January 2013). 61