A method of providing a deployment plan for a query in a distributed shared stream processing system includes storing a set of feasible deployment plans for a query that is currently deployed in the stream processing system. A query includes a plurality of operators hosted on nodes in the stream processing system providing a data stream responsive to a client request for information. The method also includes determining whether a QoS metric constraint for the query is violated, and selecting a deployment plan from the set of feasible deployment plans to be used for providing the query in response to determining the QoS metric constraint is violated.