Repository/ostree cleanup

[Dan Nicholson]

On Tue, Jan 10, 2017 at 4:53 AM, Alexander Larsson <alexl at redhat.com> wrote:
>
> I don't think it is ever unsafe to delete old versions, or am I missing
> something? I mean, clearly you can't install the versions being deleted, or
> be in the process of downloading it. However, if you have an old version
> locally installed, removing it from the remote should be ok (i.e. keep
> working locally and still be able to pull the latest version).

The problem I'm thinking of is that an old commit gets pruned and
removes an object that the concurrent pull into the repo requires. As
far as I know, there's no guard against that in ostree. Normally I
don't think this would happen, but I think it's entirely possible that
an app could ship a file 2 versions ago, remove it in the previous
version because it was not thought to be needed, and then added back
with the same content in the current version when it was determined
that it was needed. I.e., an overagressive cleanup list in the builder
manifest.

If you're pruning v-2 while pulling/committing v, it's entirely
possible that the commit will think the object exists and not commit
it again, right? I think that's what
https://bugzilla.gnome.org/show_bug.cgi?id=759442 is all about, isn't
it?

--
Dan