1. A method for processing a stream of tuples, the method comprising: receiving a stream of tuples to be processed by a plurality of processing elements operating on one or more computer processors, each processing element having one or more stream operators; identifying a breakpoint for a first stream operator, the breakpoint configured to be triggered when time for processing of a tuple by the first stream operator is predicted to exceed a threshold time; receiving, at the first stream operator, a first tuple having a set of attributes; determining, based on the set of attributes, a predicted time to process the first tuple; determining the predicted time exceeds the threshold time; triggering the breakpoint, in response to the determining the predicted time exceeds the threshold time, to pause processing of the tuple by the first stream operator; providing, in response to the triggering the breakpoint, a debugger for examining code for the first stream operator, wherein the debugger is configured to allow a user to step through execution of the code for the first stream operator; determining a section of the code for the first stream operator that is exceeding the predicted time of execution; and notifying the user when the user has stepped past the section of code.