Re: [PATCH v2 2/8] upload-pack: implement ref-in-want

From: Junio C Hamano <gitster@pobox.com>
Date: Jun 19, 2018, 20:37 UTC
Message-ID: <xmqqbmc6v7gl.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <20180619185033.GC199585@google.com>

Brandon Williams <bmwill@google.com> writes:

> I also think that we should keep this first implementation of
> ref-in-want simple and *not* include patterns, even if that's what we
> may want someday down the road.  Adding a new capability in the future
> for support of such patterns would be relatively simple and easy.

I am all for many-small-steps over a single-giant-step approach.

Show 8 quoted lines

>  The
> reason why I don't think we should add pattern support just yet is due
> to a request for "want-ref refs/tags/*" or a like request resulting in a
> larger than expected packfile every time "fetch --tags" is run.  The
> issue being that in a fetch request "refs/tags/*" is too broad of a
> request and could be requesting 100s of tags when all we really wanted
> was to get the one or two new tags which are present on the remote
> (because we already have all the other tags present locally).

I do not quite get this. Why does it have to result in a large packfile? Doesn't the requester of refs/tags/* still show what it has via "have" exchange?