Performance issues with FDK in large XML documents

Question

In my current project with FrameMaker 8 I'm experiencing severe performance issues with some FDK API calls.
The documents are about 3-8 MBytes in size. Fortmatted they cover 150-250 pages.
When importing such an XML document I do some extensive "post-processing" using FDK. This processing happens in Sr_EventHandler() during the SR_EVT_END_READER event. I noticed that some FDK functions calls which modify the document's structure, like F_ApiSetAttribute() or F_ApiNewElementInHierarchy(), take several seconds, for the larger documents even minutes, to complete one single function call. I tried to move some of these calls to earlier events, mostly to SR_EVT_END_ELEM. There the calls work without a delay. Unfortunately I can't rewrite the FDK client to move all the calls that are lagging to earlier events.
Does anybody have a clue why such delays happen, and possibly can make a suggestion, how to solve this issue? Thank you in advance.
PS: I already thought of splitting such a document in smaller pieces by using the FrameMaker book function. But I don't think, the structure of the documents will permit such an automatic split, and it definitely isn't an option to change the document structure (the project is about migrating documents from Interleaf to XML with the constraint of keeping the document layout identical).

Answer 1

FP_ApplyFormatRules sounds really good--I'll give it a try on Monday. Wonder how I could miss it, as I already tried FP_Reformatting and FP_Displaying at no avail?! By the way, what is actually meant with FP_Reformatting (when I used it I assumed it would do exactly what FP_ApplyFormatRules sounds to do), or is that one another of Lynne's well-kept secrets?
Thank's for all the helpful suggestions, guys. On Friday I already had my first improvements in a test version of my client: I did some (not all necessary) structural changes using XSLT pre-processing, and processing went down from 8 hours(!) to 1 hour--Yeappie! I was also playing with the idea of writing a wrapper to F_ApiNewElementInHierarchy() which actually pastes an appropriate element created in a small flow on the reference pages at the intended insertion location. But now, with FP_ApplyFormatRules on the horizon, I'm quite confident to get even the complicated stuff under control, which cannot be handled by the XSLT pre-processing, as it is based on the actual formatting of the document at run-time and cannot be anticipated in pre-processing.
--Franz