Go to this link: http://publib.boulder.ibm.com/iseries/v5r2/ic2924/index.htm
and then in the search window type “ILE concepts” without the quotes. In the window that will appear, you will see chapter 3 from a book titled “ILE Concepts” In there, they talk about activation groups.
Type in commitment control in the search area to get information on commitment control. The third result in the list I got gave me something on Concepts. The second entry was a portion from an HTML book on USB data base.
Good luck to you.