Re: [PATCH v4 0/5] Speed up unpack_trees()

> v4 has a bunch of changes
>
> - 1/5 is a new one to show indented tracing. This way it's less
>   misleading to read nested time measurements
> - 3/5 now has the switch/restore cache_bottom logic. Junio suggested a
>   check instead in his final note, but I think this is safer (yeah I'm
>   scared too)
> - the old 4/4 is dropped because
>   - it assumes n-way logic
>   - the visible time saving is not worth the tradeoff
>   - Elijah gave me an idea to avoid add_index_entry() that I think
>     does not have n-way logic assumptions and gives better saving.
>     But it requires some more changes so I'm going to do it later
> - 5/5 is also new and should help reduce cache_tree_update() cost.
>   I wrote somewhere I was not going to work on this part, but it turns
>   out just a couple lines, might as well do it now.