Preventing cascade failures in computer systems

A method prevents a cascading failure in a complex stream computer system. The method includes receiving binary data that identifies multiple subcomponents in a complex stream computer system. These identified multiple subcomponents include upstream subcomponents that generate multiple outputs and a downstream subcomponent that executes a downstream computational process that uses the multiple outputs. The method dynamically adjusts which of multiple inputs are used by the downstream subcomponent in an attempt to generate an output from the downstream subcomponent that meets a predefined trustworthiness level for making a first type of prediction. If no variations of execution of one or more functions used by the downstream subcomponent ever produce an output that meets the predefined trustworthiness level for making a first type of prediction, then computer hardware executes a new downstream computational process that produces a different second type of prediction.