Hello, as is well-known, FOP can run out of heap memory, when large documents are processed (http://xmlgraphics.apache.org/fop/0.95/running.html#memory).
I have the situation that the documents I have to process mandate a footer on each page that contains a "page X of Y" element and a TOC at the beginning of the document, i.e. FOP cannot layout the pages until all referenced page-citations are known, which is after the last page of the document. When page content is quite complicated (e.g. 2000 pages mostly full with tables), the heap space does not suffice to hold all pages until all references can be resolved, thus FOP aborts with out-of-memory. Since increasing the heap space does not always work (3 GB heap space was required in one example), I need a better solution for this. 1. "-conserve" option One alternative would be the "-conserve" option, which serializes the pages to disk and reloads them as needed. Although slow, this definitely would be a solution, if it worked, which it doesn't: Our documents include graphics (SVG, PNG), and the serialization with "-conserve" throws an exception, because some class in Batik is not serializable (e.g. "SVGOMAnimatedString" IIRR), thus the page is missing, causing FOP to abort later. Thus, Batik would have to be fixed for this. 2. Two passes Since the pages are kept because of unresolved references, one could do the same as e.g. LaTeX always did: process the document twice. In a first run, pages are discarded after layout, only the references for page-citations are kept and at the end reused for the second pass (when all pages for the citations are finally known). For the second run, these id-refs are initially loaded and no pages have to be kept. This would require more changes in FOP (and should definitely be made optional obviously). I would appreciate any comments or other suggestions ! Best regards Stephan -- Dr.-Ing. Stephan Thesing Elektrastr. 50 81925 München GERMANY Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3.5 - sicherer, schneller und einfacher! http://portal.gmx.net/de/go/atbrowser