document: Dynamic placement for clustered web applications We introduce and evaluate a middleware clustering technology capable of allocating resources to web applications through dynamic application instance placement . We define application instance placement as the problem of placing application instances on a given set of server machines to adjust the amount of resources available to applications in response to varying resource demands of application clusters . The objective is to maximize the amount of demand that may be satisfied using a configured placement . To limit the disturbance to the system caused by starting and stopping application instances , the placement algorithm attempts to minimize the number of placement changes . It also strives to keep resource utilization balanced across all server machines . Two types of resources are managed , one load-dependent and one load-independent . When putting the chosen placement in effect our controller schedules placement changes in a manner that limits the disruption to the system .
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