A streams manager determines when congestion is happening or is predicted to happen in a streaming application, and in response, unfuses one or more operators in the streaming application from its processing element. The selection of which operators to unfuse in which processing elements is made using suitable unfuse criteria, which may include selecting operators that do not maintain state, selecting operators that have a threaded port or queue preceding the operator, selecting operators at natural boundaries, and inserting queues before operators to be unfused. Once one or more operators are unfused, the streams manager can take action to enhance performance of the unfused operator(s). For example, the streams manager can allocate additional resources to the unfused operators, can create clones of unfused operators that process tuples in parallel, can move one or more unfused operators to a public cloud, etc.