Martin,

I think your workflow, AI source file + PDF output file for RIP is correct. That's how we do it where I work.
I have run two simple tests with a document that is 121in x 45in. The artwork is fairly simple. There are no high resolution images, just some solid fills and a gradient or two.

When I split the document into 4 panels, my PDF saves in 5-8sec. I can see the progress bar telling me it's saving PDF 1 of 4, then 2 of 4, etc. The resulting document is a multi-page PDF; each "panel" is its own page. That's what I would expect to see.

The art on a single artboard the same size as the art saves in about 2-3sec, just long enough to flash up a progress bar that disappears almost immediately.

There does seem to be a longer delay in saving the multi-page document. I'll look for a more complex document to test on and update this reply with findings.

--- update ---
Using a somewhat larger document, 323in x 106in, with several vector objects, clipping masks, high resolution images and text, I have results:

1-1.5min save-time for a full-artboard PDF.

3.5-4min to save the same art on 4 panels/artboards using the same PDF options.

These results are very close to your first example. I think you have a valid suggestion. I'm not sure what the developers can do to optimize but they may be able to do something. I'll vote for this one.

I never noticed this personally because we do all of our paneling of large documents in the RIP via automated workflows on that side of things.

Hi All,

I'm saving a PDF without illustrator Editing Capabilities.
So that is not the problem.

We make in illustrator our designs and need to export in a file extension to our PrintRIP software. I think PDF makes the most sense to choose. Is there a newer universal exchange extension that is not 'Legacy' ?

Yes, this option is designed for those who wants later 'open' PDF and edit them in Illustrator. Quite a lot of users find this very handy and surely will suffer if this 'mostly useless' workflow gets cut.

Yes, for both 'AI in PDF' or 'PDF in AI' the time taken is larger, depending on the number of artboards used.

Yes, CPU is barely used and this is not a CPU problem at all, but the 30-years old legacy format and a stream of data that has to be written. Some changes get made, especially for cloud docs, but legacy is legacy, and compatibility is something that has to stay.

So uncheck the compatibility option if you don't plan to re-edit your PDFs, and hope for the better with us.
Voted for the 'optimize' part :)

Saving a PDF: Are you saving with illustrator editing enabled? Much like saving an AI file with PDF compatibility, I find saving large/complex art as PDF w/ illustrator editing enabled adds extra time.

This option is mostly useless, unless you really really need to re-open the PDF in illustrator for editing later, rather than saving a source AI file for editing later.

Disregard the original comments below. I thought you were saving an illustrator file, not a PDF file.

original reply below (saving illustrator file w/ PDF compatibility)
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Are you saving with PDF compatibility turned on in the save-as dialog? See screenshot.

This option has always increased save-time for me, especially for large/complex documents heavy with raster effects or multiple large high resolution images.

It's completely useless unless you're using the ai file in inDesign or photoshop as a placed image.