Re: Sparse clones (Was: Re: [PATCH 1/2] upload-pack: support subtree packing)

[Enrico Weigelt <weigelt@metux.de>]

* Elijah Newren <newren@gmail.com> wrote:

Hi folks,


as I'm doing many backups via git (eg. hourly sql dumps), I'd 
like to cut off the history (eg. at the n'th past commit)
and reclaim the space - both on local and remote side (even
differently).

So let me propose another approach: fake-root's

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.

hmm, maybe it's even more wise to get one step back in history
and introduce fake-empty's (which also have no parents) instead
of fake-root's ? A fake-empty is imported as soon as the original
object is missing.


Of course, it's important that this feature has to be explicitly
enabled (maybe even on per-remote basis) to prevent security flaws.


cu
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 Enrico Weigelt, metux IT service -- http://www.metux.de/

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