[development] Object caching

[Khalid B]

> >> That is one hell of a menu.  Would be good if we could actually
> >> improve the menu system.  Have you looked into that?
> > I've been on the verge of bringing this up for a while.
> >
> > The issue we have with the menu is the exact same issue we had with the
> > aliases until 4.7.
> > We load the entire path alias into memory on every load.
>
> Past tense.
>
> We've replaces the one big load by a plethora of small loads. I am
> convinced this isn't a an improvement in all cases. E.g. on drupal.org,
> we got plenty of memory to burn, so the old setup probably wasn't much
> of a problem.

Memory was an issue, but not the main one.

The main issue was using PHP to create an associative array for every
page load, which bogged down everything. I installed the backport of
the 4.7 patch for a client who has a dedicated SMP server with 2GB
of RAM and it made a world of a difference there.

You can see the statistics here:

http://baaheyeldin.com/click/593/0

I agree that some scenarios (e.g. a sitemap page) where there will be a lot
of small queries, but for most pages, this is not the case, and a bottleneck
has been removed.