how to have yum prefer one dependency over others

[Kevin Kofler]

seth vidal wrote:
> On Fri, 2011-09-16 at 19:42 +0100, Richard Hughes wrote:
>> Installing 205 new i686 packages when updating the system is not
>> acceptable.
> 
> I agree with that. The cases where that occurs are all tied up in
> insufficiently specified requirements.

So you came up with this really complex heuristic in a vain attempt to 
always do the right thing without requiring changes to the packages, and now 
it does a completely wrong thing which would be straightforward to avoid, 
and suddenly it's the packages that need fixing? Huh?

> I've made the proposal for non-yum-based package managers to be removed
> from fedora.

WTF?!

If we were to keep only one depsolver, once zif is stable, which one would 
we want to keep:
* the tool written in a slow interpreted language, which cannot even be 
loaded into the process of the backend for our default package management 
GUI, requiring complex hacks to be spawned out of process and to bridge the 
language gap, or
* the tool written in the same compiled language as our default package 
management GUI (and its backend daemon) and by the same primary developer, 
which can be loaded simply as a shared library?

I know you want your own code to be used, but let's be honest…

Yum's reliance on Python is a major design flaw causing several problems for 
Fedora:
* depsolving slowness and memory use (e.g. I'm sure Python is to blame for a 
significant part of Anaconda's skyrocketing memory requirements; PackageKit 
update checks through yum are also a huge CPU and memory hog etc.),
* making Python (a huge interpreter) part of the critical path,
* upgrade issues like the infamous "yum from F10 updates has a higher EVR 
than yum from F11 GA, but is built against the old Python and won't run on 
F11" issue which was a PITA to recover from,
* inability to be loaded as a shared library into compiled programs like the 
PackageKit daemon,
* relying on the deprecated Python 2 and slowing down Python 3 adoption.

        Kevin Kofler