Re: [PATCH v2] fetch: limit shared symref check only for local branches

>
> Orgad Shaneh <orgads@gmail.com> writes:
>
> >> Another thing that is surprising is that you say this loop is
> >> expensive when there are many tags or branches.  Do you mean it is
> >> expensive when there are many tags and branches that are updated, or
> >> it is expensive to merely have thousands of dormant tags and
> >> branches?  If the latter, I wonder if it is sensible to limit the
> >> check only to the refs that are going to be updated.
> >
> > It's expensive even when *nothing* is updated. I have a repo with 44K
> > tags, 13K of the tags are annotated, 134 remote branches and 4
> > worktrees (except the main repo) with 33 local branches.
> >
> > I counted the calls to find_shared_symref - it was called 35755 times,
> > and refs_read_raw_ref was called 357585 times.
>
> That is exactly why I asked, as the above number hints that it could
> be a viable optimization to omit calls for refs whose old_ and
> new_oid are the same, just like you omit calls for refs that are not
> inside refs/heads/ in your patch, perhaps?