Fair assignment of processing resources to queued requests

This invention relates to controlling of multi-processing servers, and more particularly, to fair assignment of processing resources to queued requests in multi-processing servers. A request dispatching system is provided for dispatching requests to a system having a predetermined number of server instances. Each request has its service type. The request dispatching system uses one queue for each service type, and reserves for each queue a minimum number of server instances. In one embodiment, idle server instances may be configured on demand to serve requests of a different type.