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capabilities. You can control the servers operationally, monitor and view server health and performance, and configure the administrative console to display log files and configuration files for these servers.5.2 Virtualization, autonomic, and cloud computingWith Intelligent Management, virtualization, autonomic computing, and cloud computing are integrated into the single architectural model of WebSphere Application Server V8.5.5. The following sections describe these concepts.5.2.1 VirtualizationThis section describes the following concepts of virtualization:Application infrastructure virtualizationServer virtualizationApplication infrastructure virtualizationTypically, Java applications and resources are statically bound to a specific server. They often experience increases in load that last a short time. The most costly time for an application to become unavailable is during a period of high demand. Therefore, you must build IT infrastructures to accommodate these peaks. Normally, when systems experience normal load, a large percentage of computing capacity goes unused, making inefficient use of IT investments.By configuring application infrastructure virtualization in WebSphere Application Server with the Intelligent Management function, resources are pooled. This pool accommodates the fluctuations of workload in the environment, increasing the quality of service. You effectively break the bond between applications and the physical infrastructure on which they are hosted. Workloads are then dynamically placed and spread across a pool of application server resources, which allows the infrastructure to adapt and respond to business needs. Requests are prioritized and intelligently routed to respond to the most critical applications and users. The static relationships of an application with the server to which it is deployed is replaced with a dynamic relationship. This relationship has looser coupling of applications or resources and server instances. Instead of statically binding applications to servers or clusters, you deploy applications to dynamic clusters. These clusters are application deployment targets that can expand and contract, depending on the workload in the environment.
122WebSphere Application Server V8.5 Concepts, Planning, and Design GuideAfter you deploy applications to dynamic clusters, the placement of the applications is determined by the operational policies that you define. Autonomic managers control the placement of the server instances and how workload is routed to each application. If workload increases for a specific application, the number of server instances for the dynamic cluster that is hosting the application can increase. The application can also use available resources from other applications that are not experiencing increased workload.