ports upgrade question

[aaronvan at comcast.net]

I'm a newbie running 6.1 stable and I have what may be several simple questions: What exactly is happening when I run "make index && make readmes" after I upgrade my ports tree? Why aren't the indexes and readmes made when we run cvsup ports-supfile? Finally, why does it take so long to make what appear (to me) to be fairly small files? Thanks.

-- Aaron