Re: [PATCH v2] doc: add caveat about turning off commit-graph

> From: Kristoffer Haugsbakk <code@khaugsbakk.name>
> 
> The doc `technical/commit-graph.adoc` says that replace objects and
> commit grafts turn off commit-graph:
> 
>     Commit grafts and replace objects can change the shape of the commit
>     history. The latter can also be enabled/disabled on the fly using
>     `--no-replace-objects`. This leads to difficulty storing both possible
>     interpretations of a commit id, especially when computing generation
>     numbers. The commit-graph will not be read or written when
>     replace-objects or grafts are present.
> 
> But this isn’t mentioned in the user-facing doc. Let’s mention it on
> git-replace(1) and git-commit-graph(1).

> Interdiff against v1:
>   diff --git a/Documentation/git-replace.adoc b/Documentation/git-replace.adoc
>   index 2c0ea07724d..436a0e58caf 100644
>   --- a/Documentation/git-replace.adoc
>   +++ b/Documentation/git-replace.adoc
>   @@ -149,7 +149,8 @@ CAVEATS
>    -------
>    
>    The existence of replace objects or commit grafts turns off reading or
>   -writing to the commit-graph. See linkgit:git-commit-graph[1].
>   +writing to the commit-graph, which can cause performance issues. See
>   +linkgit:git-commit-graph[1].