The PeopleSoft Component Buffer and Component Processor

 

The PeopleSoft application is an extremely powerful and highly configurable product that runs many different applications.  Every application that is accessed online through the PeopleSoft Internet Architecture is part of a component.  When you navigate to a particular content reference or menu item to access a particular page, the Component Processor is what performs all of the activity including executing SQL, PeopleCode, loading the component/page, and filling the buffer with the necessary data that was requested.  More importantly, all of these activities happen in a specific order.

 

If you understand how the component processor works and how it allocates buffer space, than debugging, performance tuning, designing, and developing your PeopleSoft applications will be simple for you.  However, if you miss this concept or don’t fully understand it, your design and development process and your online performance will be inadequate.  In addition, it will become more difficult for you to debug your applications without understanding the component processor.

 

When you open any page in a PeopleSoft component, the system retrieves all of the data records for the entire component and stores them in one set of record buffers, organized by scroll level and then by page level. This component buffer consists of rows of buffer fields that hold data for the various records that are associated with page controls, including the primary records, related display records, derived work records, and translate table records.

The component buffer can be broken down into four different classes: 1. field – hold data for a record field 2. record – contains one or rmore fields 3. row - contains one or more records and zero or more child rowsets 4. rowset - contains one or more rows.

A rowset is a data structure that describes hierarchical data. For component buffers, think of a rowset as a scroll on a page that contains all of that scroll’s data. A level 0 rowset contains all the data for the entire component.

 

Technical Description

Because we are dealing with a 100% internet based application, there is no code on the client desktop.  So when a user clicks on a PeopleSoft content reference that points to a component where the page resides, the web server will make the call to the application server from a java servlet.  This call is made to the application server over the JOLT protocol. The application server, through a set of services, will issue SQL commands to the database that will retrieve the metadata. 

 

Basically, this data is returned to the application server, where it will be loaded into memory (or the component buffer) and used to assemble the necessary HTML to display to the user via the browser.  This data is retrieved by the component processor and loaded into the component buffer on the application server.  There is a precise manner in which all of this data is loaded into the buffer.  Once the HTML is assembled, it is sent to the web server.

 

In a nut shell, The Component Processor is the PeopleTools runtime engine that controls processing of an application from the time that a user requests a component from an application menu until the database is updated and processing of the component is complete.