[docbook-processors] Java Heap Size Errors with Saxon processor

Hi all,
 
It could be an issue out of sync - but referred the docbook-apps faqs, read the java -Xmx<yyy> settings, but still I encounter Java Heap Size errors. It chunks part of the code while it does not chunk a Chapter that has too many nesting. Is there a limit on the number of lines of XML code; size of the file or any such errors that one should be aware of.
 
I am using Saxon 6.5.3 on Windows; Docbook DTD 4.4, Docbook-XSL1.69.0
 
Thanks & Regards,
Sarah
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