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Journal of Computer Science 9 (6): 671-677, 2013 ISSN: 1549-3636 © 2013 Science Publications doi:10.3844/jcssp.2013.671.677 Published Online 9 (6) 2013 ( PERFORMANCE IMPROVEMENT IN CLOUD COMPUTING USING RESOURCE CLUSTERING 1Malathy, G., 2Rm Somasundaram and 3K. Duraiswamy 1Department of Computer Science and Engineering, KSR Institute for Engineering and Technology, Thiruchengode, TamilNadu, India 2Department of Computer Science and Engineering, SNS College of Engineering, Coimbatore, TamilNadu, India 3Department of Computer Science and Engineering, K.S. Rangasamy College of Technology, Thiruchengode, TamilNadu, India Received 2012-10-05, Revised 2013-01-19; Accepted 2013-05-30 ABSTRACT Cloud computing is a computing paradigm in which the various tasks are assigned to a combination of connections, software and services that can be accessed over the network. The computing resources and services can be efficiently delivered and utilized, making the vision of computing utility realizable. In various applications, execution of services with more number of tasks has to perform with minimum intertask communication. The applications are more likely to exhibit different patterns and levels and the distributed resources organize into various topologies for information and query dissemination. In a distributed system the resource discovery is a significant process for finding appropriate nodes. The earlier resource discovery mechanism in cloud system relies on the recent observations. In this study, resource usage distribution for a group of nodes with identical resource usages patterns are identified and kept as a cluster and is named as resource clustering approach. The resource clustering approach is modeled using CloudSim, a toolkit for modeling and simulating cloud computing environments and the evaluation improves the performance of the system in the usage of the resources. Results show that resource clusters are able to provide high accuracy for resource discovery. Keywords: Aggregation, Clustering, Cloudsim, Cloud Computing, Resources, Tasks 1. INTRODUCTION Large scale computing environments such as clouds propose to offer access to a vast collection of heterogeneous resources. A cloud is a parallel and distributed structure consisting of a group of interconnected and virtualized computers that are dynamically accessible as one or more unified computing resources (Buyya et al., 2009). The shared resources, software and information provided through the cloud to computers and other devices are normally offered as a metered service over the Internet. A user in the cloud system need not know about the place and other details of the computing infrastructure. Thus the user can comfortably concentrate on their tasks rather than utilizing time and knowledge on knowing the resources to manage the tasks. Internet is one basis of the cloud computing, therefore an unavoidable issue with Internet is that the network bottlenecks often occur when there is a large amount of data to be transferred. In this case, the complexity of resource management stick on to users and the users have normally limited management tools and authentication to deal with such issues (Armbrust et al., 2010). Clouds are classified into three categories named public clouds, private clouds and hybrid clouds (Sotomayor et al., 2009). Public clouds are publicly available remote interface for masses creating and managing resources, private clouds gives the local Corresponding Author: Malathy G., Department of Computer Science and Engineering, KSR Institute for Engineering and Technology, Thiruchengode, TamilNadu, India Science Publications 671 JCS Malathy, G. et al. / Journal of Computer Science 9 (6): 671-677, 2013 users a flexible and responsive private infrastructure to manage the workloads at their own cloud sites and the hybrid cloud enables the supplementing local system with the computing capacity from an external public cloud. Public cloud services like Google’s App Engine are open to all anywhere round the clock. An example for private cloud is the usage of GFS, map reduce and big table by Google inside the enterprise. The following are the features of cloud computing: High flexibility High security Easy to maintain Location independent Reduction in capital expenditure on hardware and software Figure 1 shows the four layer architecture of cloud computing and clouds are viewed as a large pool of computing and storage resources that are accessed through standard protocols with an abstract interface (Foster et al., 2008). Computing resources, storage resources and network resources are hardware level resources which are present in the fabric layer. Resources are virtualized to upper layer and end users as integrated resources are done in the unified resource layer. To develop and deploy platform on top of unified resources, a collection of specialized tools, middleware and services are added with the platform layer. The various applications that would be executed in the cloud environment are included in the application layer. The delivery mechanism in cloud computing is considered as services and is categorized in three different levels named; software service, platform service and infrastructure service (Armbrust et al., 2009). The Software as a Service (SaaS) is a software delivery model in that the applications are accessed by simple interface like web browser over Internet. Examples of SaaS-based services are web Mail, Google Docs, Facebook. The Platform as a Service (PaaS) gives a high-level integrated environment to build, test, deploy and host customer-created or acquired applications. Examples of PaaS-based service are Google App Engine, Engine Yard, Heroku. Infrastructure as a Service (IaaS) ensures processing, storage, networks and other fundamental computing resources to the users. Examples of IaaS-based services are Amazon EC2, IBM’s Blue Cloud, Eucalyptus, Rackspace Cloud. Clustering is a primary and cost-effective platform for executing parallel applications that computes large amount of data with the nodes of a cluster through the interconnected network. Fig. 1. Architecture of cloud computing Clustering is traditionally been used in many data mining applications to group together the statistically similar data elements. The algorithms used for clustering must not assume the existence of a standard distribution of certain parameters. The performance of the cluster for scientific applications by the use of fully utilizing computing devices with idle or underutilized resources requires the scheduling and load balancing techniques in an effective way. Some of the applications of cluster based services include 3D perspective rendering technique, molecular dynamics simulation. Moreover, the performance between the effective speed of processor and the various network resources continues to grow faster, which raises the need for increasing the utilization of networks on clusters using various techniques (Kee et al., 2005). This study is organized as follows. It reviews about the related literature and focuses on the detailed description of the proposed fault identification in tasks using checkpoint based cloud computing approach. It also details the experimental setup and analysis of the proposed approach. 2. MATERIALS AND METHODS The prior work on improving the design strategy in cloud computing is reviewed. Zhu and Agrawal (2011) proposed the use of cloud resources for a class of Science Publications 672 JCS Malathy, G. et al. / Journal of Computer Science 9 (6): 671-677, 2013 adaptive applications, where application-specific flexibility in computation is required with fixed timelimit and resource budget. The adaptive applications are maximized with Quality of Service (QoS) very precisely and by dynamically varying the adaptive parameters the value of application-specific benefit function is obtained. A multi-input multi-output feedback control model based dynamic resource provisioning algorithm is developed that adopts reinforcement learning to adjust adaptive parameters to guarantee the optimal application benefits within the time constraints. Tayal (2011) proposed a task scheduling optimization for the cloud computing system based on Fuzzy-GA which makes a scheduling decision by evaluating the entire group of task in a job queue. The fuzzy sets were modeled to imprecise scheduling parameters and also to represent satisfaction grades of each objective. GA with various components is developed on the technique for task level scheduling in Hadoop MapReduce. To obtain better balanced load execution time of tasks assigned to processors are predicted using scheduler and making an optimal decision over the entire group of tasks. Son and Sim (2012) proposed a service-level agreement while making reservations for cloud services. The presented multi-issue negotiation mechanism supports both price and time-slot negotiations between cloud agents and tradeoff between price and time-slot utilities. The agents make multiple proposals in a negotiation round to generate aggregated utility with variations in individual price and time-slot utilities. Banerjee et al. (2009) proposed an initial heuristic algorithm to apply modified ant colony optimization approach for the diversified service allocation and scheduling mechanism in cloud computing framework. The proposed optimization technique is used to minimize the scheduling throughput to service all the diversified requests according to the different resource allocator available under cloud computing environment. Wang et al. (2012) proposed a public cloud usage model for small-to-medium scale scientific communities to utilize elastic resources on a public cloud site. Also, implemented an innovative system named Dawning Cloud, at the core of which a lightweight service management layers running on top of a common management service framework. The system has been evaluated and found that Dawning Cloud saves the resource consumption to a maximum amount. Buyya et al. (2011) presented the vision, challenges and architectural elements of service level agreementoriented resource management. The architecture supports integration of market-based provisioning policies and virtualization technologies for flexible allocation of resources to applications. The performance results obtained from the working prototype system shows the feasibility and effectiveness of service level agreementbased resource provisioning in cloud systems. Kim et al. (2007) it is proposed a decentralized algorithm for maintaining approximate global load information and a job pushing mechanism that uses the global information to push jobs towards underutilized portions of the system. The system effectively balances load and improves overall system throughput. Belalem et al. (2011) proposed an algorithm to improve the quality of service of real world economy and to extend and enrich the simulator CloudSim by auction algorithms inherited from GridSim simulator. The work satisfies the users by reducing the cost of processing cloudlets and improved implementation on GridSim to reduce the time auction and to assure a rapid and effective acquisition of computing resources. The stochastic models to mitigate the risk of poor QoS in computational markets is studied (Sandholm and Lai, 2007). The computational needs are typically expressed using performance levels; hence the worstcase bounds of price distributions to mitigate the risk of missing execution deadlines. The new proposal is a model-agnostic, distribution-free both in prices and prediction errors and does not require extensive sampling nor manual parameter tuning. Hasham et al. (2011) proposed a pilot job concept that has intelligent data reuse and job execution strategies to minimize the scheduling, queuing, execution and data access latencies. By this approach, significant improvements in the overall turnaround time of a workflow can be achieved. This is evaluated using CMS Tier0 data processing workflow and then in a controlled environment. Gu et al. (2012) proposed a resource scheduling strategy based on genetic algorithm to produce best load balancing and reduces dynamic migration. To measure the overall load balancing effect of the algorithm an average load distance method is introduced. The method solves the problems of load imbalance and high migration cost after system virtual machine being scheduled. A decentralized resource discovery service that is designed to satisfy queries over an extensible set of Science Publications 673 JCS Malathy, G. et al. / Journal of Computer Science 9 (6): 671-677, 2013 per-node and inter-node measurements that are relevant to deciding on which nodes of an infrastructure to place instances of distributed applications is introduced (Oppenheimer et al., 2004). The SWORD’s operation on PlanetLab are scalable, distributed query processor for satisfying the multiattribute range queries that describe application resource requirements and its ability to support queries over not just per-node characteristics such as load, but also over inter-node characteristics such as inter-node latency. Erdil (2011) described a general purpose peer-topeer simulation environment that allows a wide variety of parameters, protocols, strategies and policies to be varied and studied. For proof utilization of the simulation environment is presented in a largescale distributed system problem that includes a core model and related mechanisms. Kee et al. (2005) described an abstraction for providing resource specification, resource selection and effective binding in a complex Virtual Grid environment. The elements include a novel resource description language and a resource selection and binding component. The goal of the binding component is efficiency, scalability, robustness to high resource contention and the ability to produce results with quantifiable high quality. The aggregated result for San Fermin node by swapping data with other nodes to dynamically create its own binomial tree (Cappos and Hartman, 2008). San Fermin node is a system for aggregating large amounts of data from the nodes of large-scale distributed systems. Because of the binomial tree the node are resilient to failures and ensures that the internal nodes of the tree have high capacity and reduction in completion time. A compromised-time-cost scheduling algorithm which considers the characteristics of cloud computing to accommodate instance-intensive cost-constrained workflows by compromising execution time and cost with user input enabled on the fly. Simulations show that the algorithm can achieve a lower cost than others while meeting the user-designated deadline or reduce the mean execution time than others within the userdesignated execution cost. A technique for predicting availability and test them using traces taken from three distributed systems (Mickens and Noble, 2006). Also, described three applications of availability prediction. The first availability-guided replica placement, reduces object copying in a distributed data store while increasing data availability. The second shows how availability prediction can improve routing in delay-tolerant networks. The third combines availability prediction with virus modeling to improve forecasts of global infection dynamics. 2.1. Resource Identification and Clustering In recent years the use of cloud systems for scientific computations, data sharing and dissemination are increasing in a rapid manner. Each cloudlet available in this distributed system will differ widely in resource capabilities such as CPU performance, bandwidth, memory availability and so on. So identifying the resource is needed to satisfy the application requirements. The traditional resource discovery systems use only the recent cloudlet usage information for scalability and simplicity. This s proposes a resource discovery approach based on resource usage information from cloudlets both in temporal and spatial manner. The temporal manner deals with the resource usage in a long-term pattern and spatial manner deals with the number of cloudlet with similar usage patterns. A resource cluster represents the resource usage distribution for a group of cloudlets with similar resource usages. Resource cluster requires two complementary techniques to capture the temporal details of the cloudlets. The two techniques are resource usage histogram and clusteringbased resource aggregation. Histograms gives information about the statistical usage of resource capacities and the aggregation is used to achieve compact representation of a set of similar cloudlets for scalability. That is the resource clusters are used to find group of cloudless satisfying a common requirement. To handle the various resource requirement specifications the resource usage histogram is used and its associated observation is viewed at time period‘t’. The histogram shown in Fig. 2 illustrates the resource capacity distributions in the cloudlets from observations over the past‘t’ units. Separate histogram is to be used for each resource types like CPU performance, bandwidth, memory availability and for each time granularities like hour, day, week, month, year. The histogram representation gives the information about the percentiles for a particular resource capacity and also histogram helps us to preserve all usage data. That is the histogram can be used to capture different tolerances even if different applications specify different resource capacity requirements. Thus statistical information for each cloudlet would be represented by several histograms, corresponding to various resources and time scales. Science Publications 674 JCS Malathy, G. et al. / Journal of Computer Science 9 (6): 671-677, 2013 Fig. enfocar la importancia de la producción mediática de los niños en su descubrimiento del mundo, sobre todo utilizando el periódico escolar y la imprenta. Asimismo las asociaciones de profesores trabajaron en esta línea e incluso la enseñanza católica se comprometió desde los años sesenta realizando trabajos originales en el marco de la corriente del Lenguaje Total. Páginas 43-48 45 Comunicar, 28, 2007 En el ámbito de los medios, también desde el principio del siglo XX hay ciertas corrientes de conexión. Pero es a lo largo de los años sesenta cuando se constituyeron asociaciones de periodistas apasionados por sus funciones de mediadores, que fomentaron la importancia ciudadana de los medios como algo cercano a los jóvenes, a los profesores y a las familias. Así se crearon la APIJ (Asociación de Prensa Información para la Juventud), la ARPEJ (Asociación Regional de Prensa y Enseñanza para la Juventud), el CIPE (Comité Interprofesional para la Prensa en la Escuela) o la APE (Asociación de Prensa y Enseñanza), todas ellas para la prensa escrita Estas asociaciones fueron precedidas por movimientos surgidos en mayo de 1968, como el CREPAC que, utilizando películas realizadas por periodistas conocidos, aclaraba temas que habían sido manipulados por una televisión demasiado próxima al poder político y realizaba encuentros con grupos de telespectadores. cipio del siglo XX, y nos han legado textos fundadores muy preciados, importantes trabajos de campo y muchos logros educativos y pedagógicos. La educación en medios ha tenido carácter de oficialidad de múltiples maneras, aunque nunca como una enseñanza global. Así la campaña «Operación Joven Telespectador Activo» (JTA), lanzada al final de los años setenta y financiada de manera interministerial para hacer reflexionar sobre las prácticas televisuales de los jóvenes, la creación del CLEMI (Centro de Educación y Medios de Comunicación) en el seno del Ministerio de Educación Nacional en 1983, la creación de la optativa «Cine-audiovisual» en los bachilleratos de humanidades de los institutos en 1984 (primer bachillerato en 1989) y múltiples referencias a la educación de la imagen, de la prensa, de Internet. La forma más visible y rápida de evaluar el lugar de la educación en medios es valorar el lugar que se le ha reservado en los libros de texto del sistema educa- 2. Construir la educación en los medios sin nombrarla El lugar que ocupa la edu- La denominación «educación en medios», que debería cación en los medios es muy ambiguo, aunque las cosas están cambiando recientemente. entenderse como un concepto integrador que reagrupase todos los medios presentes y futuros, es a menudo percibida En principio, en Francia, co- por los «tradicionalistas de la cultura» como una tendencia mo en muchos otros países, la educación en los medios no es hacia la masificación y la pérdida de la calidad. una disciplina escolar a tiempo completo, sino que se ha ido conformado progresivamente a través de experiencias y reflexiones teóricas que han tivo en Francia. Una inmersión sistemática nos permi- permitido implantar interesantes actividades de carác- te constatar que los textos oficiales acogen numerosos ter puntual. Se ha ganado poco a poco el reconoci- ejemplos, citas, sin delimitarla con precisión. miento de la institución educativa y la comunidad es- colar. Podemos decir que ha conquistado un «lugar», 3. ¿Por qué la escuela ha necesitado casi un siglo en el ámbito de la enseñanza transversal entre las dis- para oficilializar lo que cotidianamente se hacía en ciplinas existentes. ella? Sin embargo, la escuela no está sola en esta aspi- Primero, porque las prácticas de educación en me- ración, porque el trabajo en medios es valorado igual- dios han existido antes de ser nombradas así. Recor- mente por el Ministerio de Cultura (campañas de foto- demos que no fue hasta 1973 cuando aparece este grafía, la llamada «Operación Escuelas», presencia de término y que su definición se debe a los expertos del colegios e institutos en el cine ), así como el Minis- Consejo Internacional del Cine y de la Televisión, que terio de la Juventud y Deportes que ha emprendido en el seno de la UNESCO, definen de esta forma: numerosas iniciativas. «Por educación en medios conviene entender el estu- Así, esta presencia de la educación en los medios dio, la enseñanza, el aprendizaje de los medios moder- no ha sido oficial. ¡La educación de los medios no apa- nos de comunicación y de expresión que forman parte rece oficialmente como tal en los textos de la escuela de un dominio específico y autónomo de conocimien- francesa hasta 2006! tos en la teoría y la práctica pedagógicas, a diferencia Este hecho no nos puede dejar de sorprender ya de su utilización como auxiliar para la enseñanza y el que las experiencias se han multiplicado desde el prin- aprendizaje en otros dominios de conocimientos tales Páginas 43-48 46 Comunicar, 28, 2007 como los de matemáticas, ciencias y geografía». A pe- mente en todas las asignaturas. Incluso los nuevos cu- sar de que esta definición ha servido para otorgarle un rrículos de materias científicas en 2006 para los alum- reconocimiento real, los debates sobre lo que abarca y nos de 11 a 18 años hacen referencia a la necesidad no, no están totalmente extinguidos. de trabajar sobre la información científica y técnica y En segundo lugar, porque si bien a la escuela fran- el uso de las imágenes que nacen de ella. cesa le gusta la innovación, después duda mucho en Desde junio de 2006, aparece oficialmente el tér- reflejar y sancionar estas prácticas innovadoras en sus mino «educación en medios» al publicar el Ministerio textos oficiales. Nos encontramos con una tradición de Educación los nuevos contenidos mínimos y las sólidamente fundada sobre una transmisión de conoci- competencias que deben adquirir los jóvenes al salir mientos muy estructurados, organizados en disciplinas del sistema educativo. escolares que se dedican la mayor parte a transmitir Este documento pretende averiguar cuáles son los conocimientos teóricos. La pedagogía es a menudo se- conocimientos y las competencias indispensables que cundaria, aunque los profesores disfrutan de una ver- deben dominar para terminar con éxito su escolaridad, dadera libertad pedagógica en sus clases. El trabajo seguir su formación y construir su futuro personal y crítico sobre los medios que estaba aún en elaboración profesional. Siete competencias diferentes han sido te- necesitaba este empuje para hacerse oficial. nidas en cuenta y en cada una de ellas, el trabajo con Aunque el trabajo de educación en los medios no los medios es reconocido frecuentemente. Para citar esté reconocido como disciplina, no está ausente de un ejemplo, la competencia sobre el dominio de la len- gua francesa definen las capa- cidades para expresarse oral- La metodología elaborada en el marco de la educación en mente que pueden adquirirse con la utilización de la radio e, medios parece incluso permitir la inclinación de la sociedad incluso, se propone fomentar de la información hacia una sociedad del conocimiento, como defiende la UNESCO. En Francia, se necesitaría unir el interés por la lectura a través de la lectura de la prensa. La educación en los medios las fuerzas dispersas en función de los soportes mediáticos y orientarse más hacia la educación en medios que al dominio adquiere pleno derecho y entidad en la sección sexta titulada «competencias sociales y cívi- técnico de los aparatos. cas» que indica que «los alum- nos deberán ser capaces de juz- gar y tendrán espíritu crítico, lo que supone ser educados en los las programaciones oficiales, ya que, a lo largo de un medios y tener conciencia de su lugar y de su influencia estudio de los textos, los documentalistas del CLEMI en la sociedad». han podido señalar más de una centena de referencias a la educación de los medios en el seno de disciplinas 4. Un entorno positivo como el francés, la historia, la geografía, las lenguas, Si nos atenemos a las cifras, el panorama de la las artes plásticas : trabajos sobre las portadas de educación en medios es muy positivo. Una gran ope- prensa, reflexiones sobre temas mediáticos, análisis de ración de visibilidad como la «Semana de la prensa y publicidad, análisis de imágenes desde todos los ángu- de los medios en la escuela», coordinada por el CLE- los, reflexión sobre las noticias en los países europeos, MI, confirma año tras año, después de 17 convocato- información y opinión rias, el atractivo que ejerce sobre los profesores y los Esta presencia se constata desde la escuela mater- alumnos. Concebida como una gran operación de nal (2 a 6 años) donde, por ejemplo, se le pregunta a complementariedad source of circulating FGF-21. The lack of association between circulating and muscle-expressed FGF-21 also suggests that muscle FGF-21 primarily works in a local manner regulating glucose metabolism in the muscle and/or signals to the adipose tissue in close contact to the muscle. Our study has some limitations. The number of subjects is small and some correlations could have been significant with greater statistical power. Another aspect is that protein levels of FGF-21 were not determined in the muscles extracts, consequently we cannot be sure the increase in FGF-21 mRNA is followed by increased protein expression. In conclusion, we show that FGF-21 mRNA is increased in skeletal muscle in HIV patients and that FGF-21 mRNA in muscle correlates to whole-body (primarily reflecting muscle) insulin resistance. These findings add to the evidence that FGF-21 is a myokine and that muscle FGF-21 might primarily work in an autocrine manner. Acknowledgments We thank the subjects for their participation in this study. Ruth Rousing, Hanne Willumsen, Carsten Nielsen and Flemming Jessen are thanked for excellent technical help. The Danish HIV-Cohort is thanked for providing us HIV-related data. 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