Re: A new metric for source package importance in ports

Johannes Schauer wrote:
> Hi,
>
> the following is a report of a successful implementation of what I have been
> talking about with Niels Thykier during debconf13. The question was how
> important it is for a source package to be compilable or exist in the first
> place given an incomplete port which is in the process of being bootstrapped.
> This work is solving a different purpose than the identification of "key
> packages" by Lucas Nussbaum [1]. Instead of attaching a binary value to each
> source package, this method is associating integer values to them. Once
> bootstrapping of the whole archive becomes more important or even possible in
> real life through an implementation of build profiles, this heuristic could be
> used to further extend the meaning of "key packages" as well.
One problem with these metrics is that you get source packages whose
importance is artifically inflated because of the way our source
packages work. If anything in a source package needs x then the whole
source package has to build-depend on x.  Even if x is only needed for
some perhipheral functionlity that could easilly be removed in the event
that x was unavailable (either on a particular port or in general). In
the case of libraries there may be a binary dependency too for rarely
used fuctionality.

For example some of the mesa libraries drag in libwayland0 which means
wayland ends up with a very high importance even though afaict hardly
anyone uses it right now.

Another big example is languages. Lots of packages build language
bindings for lots of languages dragging those languages into the
"important set".

So these metrics are a good guide to what packages are unimportant
but to determine whether a package is really important or just
psuedo-important still requires human judgement.