> I was under the impression portage was "slow" (relative to other package management tools) due to the fact that it built everything from source (for which it uses make). Where is the Python bottleneck?

I was talking about the overhead of making the list of packages to update/install. Pretending to install a simple package takes 7 seconds. Pretending to update takes 13 seconds. That's a very long time, because I might want to review the list of packages and make some changes, and every time I have to wait 13 seconds.

The compiling part is true, but that is not supervised.