From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: Question about how git determines the minimum packfile for a push.
Date: Sun, 26 Apr 2015 21:39:32 -0700
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To: Brad Litterell <brad@evidence.com>
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On Sun, Apr 26, 2015 at 5:41 PM, Brad Litterell <brad@evidence.com> wrote:
>
> Is it possible git is not computing the delta correctly?
> Or does git only look at the top-level commit objects to figure out what to
> include in the push packfile?

We walk the commit graph backwards to discover the common ancestries to
minimize the network cost when fetching, but I do not think the
reverse direction
has such smart in the protocol.

If you fetch (not "pull") first to remote tracking branches and then push, that
probably will reduce the transfer, as the side that pushes is the only one that
decides what objects are sent in "git push -> git receive-pack" direction.