Background processing during import

Hi.

I am concerned about background processing when importing data.

At the time of import, a comment about the process being executed is displayed in the window, but the following two processes are taking a long time.

・Evaluating

・Waiting for "server name"

What kind of processing is being performed when the above two are displayed?

I would like to use it as a reference when explaining to users, so if anyone knows it, I would appreciate it if you could be a professor.

Thank you.