1. A method of storing data stream in a stream application composed from a plurality of processing elements executing on one or more compute nodes, the method comprising: loading a trigger rule on a first processing element in the plurality of process elements, the trigger rule including a trigger condition; receiving a first tuple at the first processing element from the data stream; and upon determining the first tuple received at the first processing element satisfies the trigger condition, performing a processing action on at least one of the first tuple and the data stream, wherein the trigger rule defines the processing action to be performed.