Repository/ostree cleanup

[Alexander Larsson]

On Wed, 2017-01-11 at 14:39 -0600, Dan Nicholson wrote:
> 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?

Well, thats a slightly different case though. Pruning a repo while
commitíng to it, and yes, that is not safe for that reason.

It should be safe to prune an old commit from a repo while at the same
time pulling another commit *from* that repo.

-- 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
       alexl at redhat.com            alexander.larsson at gmail.com 
He's a gun-slinging vegetarian stage actor who knows the secret of the 
alien invasion. She's a plucky mutant stripper married to the Mob. They 
fight crime!