A novel and useful method, system and framework for extending event processing pattern language to include constructs and patterns in the language to support historical patterns and associated retrospective event processing that enable a user to define patterns that consist of both on-line streaming and historical (retrospective) patterns. This enables entire functions to be expressed in a single pattern language and also enables event processing optimization whereby function processing is mapped to a plurality of event processing agents (EPAs). The EPAs in turn are assigned to a physical processor and to threads within the processor.