How do I speed up the save for huge PDF files?

Q: I run into a perfomance issue when saving huge PDF files.

Currently I am creating a 18,000+ page pdf. It takes long time for
the save function to complete. Is there any way to speed up the
save? Here is the call.
doc.Save(cardToFileName[key], SDFDoc.SaveOptions.e_linearized);

Any Ideas?
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A: To speed-up the save you could pass 0 instead of e_linearized.
Please let me know if this helps.

Yes, I did find yesterday that this took the save time down by a
factor of 10.