1. A method for processing a stream of tuples, comprising: receiving a stream of tuples to be processed by a plurality of processing elements operating on one or more computer processors, wherein one or more poison tuples from the stream of tuples has one or more attributes with values that cause adverse performance in a processing element; generating a model of performance for processing the stream of tuples at runtime; predicting a parameter of the one or more poison tuples from the stream of tuples, the parameter indicating a potential of a processing element for adverse performance when processing one or more poison tuples, the predicting including using the model; and modifying processing of the one or more poison tuples if the parameter falls outside a parameter threshold.