[pacman-dev] do we need requiredby?

[Aaron Griffin]

On Nov 12, 2007 2:18 PM, Travis Willard <travis at archlinux.org> wrote:
> On Mon, 12 Nov 2007 14:08:07 -0600, Aaron Griffin wrote
> > On Nov 12, 2007 10:21 AM, Nagy Gabor <ngaba at bibl.u-szeged.hu> wrote:
> > > So I will create a patch for killing requiredby soon. The patched pacman will be
> > > compatible with the old dbs; however, old pacmans with new dbs will fail.
> > > What do you say? Any contras? [my patch would simulate alpm_pkg_get_requiredby
> > > with compute_requiredby]
> >
> > Just to make sure I understand you - you want to fully remove
> > REQUIREDBY from the DB and compute it every time.
> >
> > It will be a little slower, BUT, it will help us in a few ways:
> >
> > 1) we don't need REQUIREDBY all that often. It's only used in removal,
> > and replace functionality if I understand correctly. The performance
> > hit will not be that big in this case (removal happens far less often
> > than addition).
> > 2) Our package structures will shrink in size, which is always good
>
> 3) Computing requiredby every time will ensure (if the computation is done
> right) that requiredby will always be correct.  Even after -Rd operations
> followed by subsequent -S operations and other crazy things.  Basically, less
> bookkeeping to do on install/remove.

I knew I had more points in my head! This was one of them - preventing
DB corruption.

4) Less disk writes, as we actually have to write, compute, and
rewrite the entry, if memory serves me correctly.