Re: [PATCH v2 3/3] glossary: add reachability bitmap description

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 25, 2022, 15:53 UTC
Message-ID: <xmqqpmefoq6u.fsf@gitster.g>
In-Reply-To: <c9e90df3-6f70-6422-00db-beb7afda0439@github.com>

Derrick Stolee <derrickstolee@github.com> writes:

> The one thing I will say is that there can be multiple .bitmap
> files, but Git will only use one of them. Not sure if that is
> worth being pedantic about here, though.

That matches my understanding, but "can be" is less of the norm these days, no? "repack -b" would refuse without "-a" so we may have more than one by accident, or am I missing a common scenario that we do perfectly normal things and still end up with multiple?

I agree with you that it probably is a good idea to say there can be, so that the readers do not have to alarmed.

      Only one '.bitmap' file (which stores multiple reachability
      bitmaps) per repository is used in a repository (note. it is
      not wrong to have more than one).  The bitmap file may belong
      to either one pack, or the repository's multi-pack index (if
      it exists).

But then the readers who do have more than one would next think "how do I get rid of the ones that are not used? they are wasting my precious disk space". So I also am not sure if it helps to write more. "It is generally true that.." white lie may be better than technical correctness in this case.

> We'll need to keep this glossary section in mind in case things
> change (such as "at most one bitmap file").

True.

Thanks.