Hi jesfrigon,
Since I have no idea about your setup, the question's answer could be very long and just guesses. This is not what I do here. I do not answer from memory when I have a file, nor without testing if that works with the current version. Your 16GB excludes this sadly.
To get to 16GB seems odd, but again, perhaps that is what you need if your setup is not possible in another way.
This leads me to problem-solving strategies, which are the skills that 3D artists need to have.
Here are a few: (Surely not complete.)
• Reverse Engineer: Deconstructing the Problem.
• Algorithmic Approach: Step-by-Step Solutions.
• Pattern Recognition: Finding the Underlying Structure.
• Hypothesis Test: Proving or Disproving Assumptions.
• Constraint Analysis: Working Within Limits.
• Root Cause Analysis: Digging to the Core.
• Scenario Planning: Preparing for All Outcomes.
• Prioritization Protocol: Focusing on What Matters.
• Simplification Strategy: Reducing Complexity.
• Visualization Technique: Seeing the Solution.
What happens if… is one core question here.
One method is checking the backup sequence you typically get while setting up a large project.
When the size jumped is an indicator.
Another method is to create a copy and delete all parts that you suspect are driving the size up, saving it into a new file, and checking the size.
Could a different method of creating the scene (RS Proxy, XRef) have been used as a problem-solving question?
Perhaps we should avoid using Vertext maps and use image-based maps.
Are all the details needed, e.g., the Foreground, Middle Ground, background evaluation, and Level of Detail, or even 3D with image replacement?
Typically, I ask for a file, but I will not download anything larger than a few hundred MB, which is surely not a 16GB file. Just to avoid work on your side.
Create a new scene, save incrementally while building up a mini version of the scene, and, as mentioned above, check when the size jumps. With that jump, typically, one of the reasons is clear.
Please search for an alternative, (Sprites/Cards, Digital Matte painting for Background. etc. Since I don't know where you created 16GB of Data, which might unfold even more when opened, you need to explore that)
Perhaps switching off all Generators and keeping the Time slider at zero while clearing Chaches will also help. (Yes, that is the guessing part, and I stop here.
If that has found a solution, move on and see if the steps towards completing your mini setup create similar jumps in size. Repeat.
All the best
