Re: [PATCH v2 0/7] Speed up mirror-fetches with many refs

> Changes compared to v1:
> 
>     - Patch 1/7: I've applied Stolee's proposal to only
>       opportunistically load objects via the commit-graph in case the
>       reference is not in refs/tags/ such that we don't regress repos
>       with many annotated tags.
> 
>     - Patch 3/7: The return parameter of the iterator is now const to
>       allow further optimizations by the compiler, as suggested by
>       René. I've also re-benchmarked this, and one can now see a very
>       slight performance improvement of ~1%.
> 
>     - Patch 4/7: Added my missing DCO, as pointed out by Junio.
> 
>     - Patch 5, 6, 7: I've redone these to make it clearer that the
>       refactoring I'm doing doesn't cause us to miss any object
>       connectivity checks. Most importantly, I've merged `fetch_refs()`
>       and `consume_refs()` into `fetch_and_consume_refs()` in 6/7, which
>       makes the optimization where we elide the second connectivity
>       check in 7/7 trivial.