From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Truncating history (Re: Sparse clones)
Date: Fri, 13 Aug 2010 14:19:54 -0500
Message-ID: <20100813191954.GA2003@burratino>
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 <20100813173147.GB27540@nibiru.local>
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Hi,

Enrico Weigelt wrote:

> Fake-roots are special refs that declare certain commit objects
> as root-commits). Each time git walks down the history, it checks
> whether the current commit is an fake-root and so treats it as
> having no ancestor. That should be generic enough let everything
> else (commit, push, gc, etc) work as usual.
> 
> The only tricky point is when to update remote fake-roots: the
> remote should not cut off my local repo (unless explicitly asked).
> So remote fake-roots should only be imported if the local/receiving
> side has not the dropped commits anymore.

You may be interested in grafts and replacement refs; see
git-filter-branch(1) and git-replace(1) for some hints.

Good luck,
Jonathan