[Catalog-sig] start on static generation, and caching - apache config.

["Martin v. Löwis"]

> If they're effectively static, why can't Apache cache them?

That's easy to answer: nobody told Apache to do that
(and I don't know how to tell it to).

René's approach currently is to generate the files explicitly
on disk, and then have Apache return them always from disk.

> Shouldn't
> we be able to simply add Last-Modified/If-Modified support to the PyPI
> output, and enable Apache's disk caching for non-logged-in users?

How precisely would that work? I.e. what software should put what
header into what place, and how would the cache then find out that
the real data have changed?

> While that's not necessarily as fast as static page generation, it's a
> lot less complex to get right, and it saves the main piece of CPU load:
> i.e., doing SQL queries and actually generating the page.

I'm not convinced yet that this is where the time is spent (seeing
actual profiling data would convince me). I have learned to never
ever guess what precisely is consuming cycles in a piece of software.

> Pages that pertain to more than one package might be a bit more complex
> to do this on, but if I understand correctly it's mainly the
> package-specific pages we're concerned with here, correct?

I'm not convinced of that, either.

Regards,
Martin