pthcincy,
if you are working on big set of records avoid using appendToDocumentList service. This service do a full allocation of object.length+1 and a copy of the contents on each call. This is fine for arrays with tens or maybe hundreds of items, but bogs down when called often on large arrays.
Instead add your IData to linked list and convert it to array after the loop. PS utilites has these services provided under list folder.
My two cent !
#webMethods#Flow-and-Java-services#Integration-Server-and-ESB