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

>> 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.