systemd acceptance, packaging guidelines (was Re: systemd and changes)

[Matt McCutchen]

On Tue, 2010-08-24 at 23:31 +0200, Lennart Poettering wrote:
> On Tue, 24.08.10 16:38, Bill Nottingham (notting at redhat.com) wrote:
> > Lennart Poettering (mzerqung at 0pointer.de) said: 
> > > > - init shall support a mechanism to re-exec itself to not cause dirty
> > > >   inodes on shutdown; initscripts will use this method on shutdown.
> > > 
> > > This is bad. While we support this just fine I think it is a really bad
> > > idea to reexec init at shutdown. What's the point of this, can you elaborate on
> > > this? This smells to me as a workaround for brokeness in older init
> > > systems, and I don't see a reason why reexecing itself would be
> > > necessary for systemd.
> > 
> > If the libraries or binaries used by systemd are replaced during runtime,
> > and it is not re-executed on shutdown, the filesystem will have busy inodes
> > on shutdown. (If you'd like to take the filesystem semantics up with the
> > kernel, feel free to tilt at that windmill.)
> 
> Hmm, so this is about files that are deleted but still mapped by init,
> and which can only be deleted when init stops referencing them, but that
> is required to remount the fs r/o? Did I get this right?

Yes, that's right.

> I am not really convinced that reexecing is the right answer for this
> problem. But well, since this already works anyway I guess this doesn't
> really matter too much.

Indeed, it's a hack, but there's no better option in sight, so I don't
see the point in complaining.

> > Sure, I suppose individual maintainers want to push their code over the wall and
> > then sit in their silo and claim 'that's not my problem' and 'someone else
> > needs to fix that', well, that's their right to be lame. But we, as Fedora,
> > as producers of a product that we ship to our users, don't have that luxury.
> 
> But you enable them to block out change. For example, if somebody
> refuses to merge a patch that adds a systemd equivalent for an upstart
> config hook he has, he can sink the whole systemd in fedora project.

If that happens, take it to FESCo.

-- 
Matt