Understanding Prioritization

[Gustavo Niemeyer]

Hello Eli,

> Is there anyway of getting a relatively indepth understanding of how to set 
> prioritization. I'm using fc4 and have been managing my packages with 
> apt-get. However, one of a number of the repositories that I rely on has 
> discontinued support for apt-get. Prioritization in apt-get is brilliant and 
> works. I need it to work as well in smart.

A package priority is currently considered in two distinct moments:

1) When an upgrade operation is being prepared. If a package has a
   higher priority, it is immediately considered as being an
   upgrade/downgrade candidate over any other package connected to
   that one by an "upgrades" relation (by either having the same name,
   or having an "obsoletes" relation, in the case of RPM packages).

2) When there are multiple alternatives for satisfying a dependency,
   a package having a higher priority has more chances of being
   selected to satisfy the dependency. That's not an isolated
   decision though. For instance, if installing a package with a
   higher priority would mean including dozens of other dependencies,
   the priority *difference* between the higher priority package and
   the other packages should be big enough to justify the change.

Point (1) behaves in a quite similar way to APT's pinning feature. On
the other hand, point (2) doesn't.  In case you try it, your feedback
on the current beahvior will be welcome.

> Any additional insight relative to the FAQ would be very very much
> appreciated.

That's a good item for the FAQ indeed.

-- 
Gustavo Niemeyer
http://niemeyer.net