I want to post about involve monitoring activities at Oracle R12 Output Post Processor.
In Oracle R12, there are program of Concurrent Processing. Concurrent Processing now uses the Output Post Processor (OPP) to enforce post-processing actions for concurrent requests.Post-processing actions are actions taken on concurrent request output. An example of a post-processing action is that used in Concurrent Processing support of XML Publisher.
If a request is submitted with an XML Publisher template specified as a layout for the concurrent request output, then after the concurrent manager finishes running the concurrent program, it will contact the OPP to apply the XML Publisher template and create the final output.
And i got the reference from this url.