[NEW IDEA] Automatic removal of dependencies

[Jeff Spaleta]

On 4/22/06, Mark Rosenstand <mark at borkware.net> wrote:
> Of course this is where the "explicitly installed" attribute is useful.
> I assume glibc, grub, udev etc. are all explicitly installed by
> anaconda.

The smallest group of packages which you can be sure were explicitly
installed are the mandatory members of the "Core" group in the
comps.xml file for Fedora Core.  Since Fedora's installer has the
ability to use kickstart for highly customized installs, you can not
be reasonable sure that any other specific package will be
"explicitly" installed.  My vixie-cron example illustrates that
problem. vixie-cron is a mamber of the "Base" group which kickstart
installs may or may not use so some installs may not "explicitly" ask
vixie-cron to be installed and it may be pulled in by sysstat. Or it
maybe explicitly removed at some later day and then pulled in by a
sysstat install. "explicit" dependancy marking is an unreliable
measure of how actively that dependacy is being used on the system and
can not be the basis of a robust automatic dependancy removal process.

I have no problem with a set of tools that help admins review leaf
nodes in their packageset. But I have concern for any tool that offers
to automatically remove leaf nodes...based solely on information which
can be tracked by the package management system..  I firmly belief
that leaf node removal requires active human review and the process
should not be condensed into a set of simplified y/n/cancel dialogs.  
Things like how frequently/recently the files associated with the
package have been accessed by un-dependant executables and libraries
(excluding prelink) are important factors to consider.. factors which
live outside the available package management information.

-jef