How can I tell what's happening during Compile? It's taking way too long, and doing too many things.

I have a simple, one scene game that's a helicopter simulator. There's a terrain, the helicopter prefab, Missile prefab I wrote, machine gun prefab, and the scripts to run them. There are also a few models of buildings I've downloaded from the internet to display on the ground, but at the moment, they're disabled. I don't suppose that matters when it's compiling. But when I compile, it shows a Building Player box with the percentage bar. Here's the thing, it's saying "11 Clustering" and a ton of jobs! So it's message is something like "5/11 Clustering | 189 jobs".

I don't know what a job is, or why there would be over 100 of them, or what a Cluster is, or why I have 11 of them, but it's taking hours to compile, and I would gladly get rid of whatever is causing that delay. Is there a means to determine that?