From: Simon Richter <simon.richter@hogyros.de>
Date: Mon, 22 Sep 2025 10:41:23 GMT
Subject: Re: Could Git be smarter about object reuse?
Message-ID: <f478fc6f-77ab-4d4e-a8d9-2d44622ba8dd@hogyros.de>
In-Reply-To: <pmKix6R7b3WVLrcK6ig1Lh7RhrB5G4Hm5yam_fEoC839aatB-OjJEmSJJ-weErGEnt4Mvgf5slxgu6Pm1xlGZ4mr_i4MIAAEMYy8DjJnWgk=@calamity.inc>

Hi,

On 9/22/25 7:06 PM, Sainan wrote:

> It's especially annoying because I know the server already has basically all the blobs needed and hence would only need to receive the commit and tree objects.

Git already does this. The receiver sends a list of commits it has, and 
the sender omits all objects (of any kind) that are reachable from any 
of these.

For this to work, the sender needs to be able to follow the commits from 
these references, so this does not work properly if the sender is 
operating from a shallow clone, or is missing branches, because the 
receiver only sends a list of branch tips (and, if the receiver is 
shallow, missing commits), not a full list of objects present, because 
that would be a lot.

    Simon