Re: [PATCH] Introduce light weight commit annotations

[Junio C Hamano <gitster@pobox.com>]

Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

> With the provided script, edit-commit-annotations, you can add
> after-the-fact annotations to commits, which will be shown by
> the log if the config variable core.showannotations is set.
>
> The annotations are tracked in a new ref, refs/annotations/commits,
> in the same fan-out style as .git/objects/??/*, only that they only
> exist in the object database now.
>
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---
>
> 	I have the hunch that this will be relatively fast and scalable,
> 	since the tree objects are sorted by name (the name being the
> 	object name of the to-be-annotated commit).

The entries of tree are sorted but not necessarily of uniform
length so you end up needing linear search anyway.  The fan-out
would help with the current tree objects.

It will hurt _if_ we introduce a new tree object format that
would give you a quick random-access at an entry, but it is
premature to worry about that now.