A couple of rants about Launchpad

[Colin Watson]

On Fri, Mar 06, 2009 at 01:45:34PM +0000, David Gerard wrote:
> 2009/3/6 Colin Watson <cjwatson at ubuntu.com>:
> > On Fri, Mar 06, 2009 at 09:48:32AM +0800, Christopher Chan wrote:
> >> You can at least ensure that certain basic configuration tools work
> >> before you put them in a release. It gives a very bad image when I have
> >> to walk a person through the terminal running commands to work around a
> >> bug in a configuration tool for a basic need.
> 
> > As above, we do test all sorts of things including configuration tools
> > and make sure they work. Obviously when something slips through for some
> > subset of people the natural conclusion for them is that we didn't
> > bother testing configuration tools at all, but that isn't the case. Our
> > testing does have holes and we're always trying to improve it, but it is
> > not absent by any means.
> 
> In my experience, dist-upgrade is more often problematic than not. I
> recently tried taking a laptop through 6.06->8.04->8.10 (I could only
> find a 6.06 CD on hand). LTS to LTS to current should be flawless; I
> had to do command-line stuff with apt-get to get it to work smoothly.
> That's just not good enough.

Please, please, please report this kind of thing, ideally sooner rather
than later. We can often work around problems in the upgrade tool even
after release.

Over time we have been cranking up the amount of automatic testing we do
of this kind of thing. I think it nowadays involves some tentacled
madness that installs a random selection of packages on each iteration
and then complains if the upgrade breaks ...

> I recently had to disrecommend Ubuntu on servers at work because the
> desktop dist-upgrade just isn't up to scratch IME, and that just
> doesn't bode well enough for servers.

FWIW server upgrades actually tend to be rather simpler in terms of the
dependency structures involved, which is the main variable.

> Debian famously manages dist-upgrades flawlessly. What are they doing
> that we aren't?

Debian doesn't do this flawlessly either; witness the notorious
/usr/bin/X11 -> /usr/bin move that required complicated manual
intervention from anyone with X packages installed that weren't in the
enormous Conflicts line.

Beyond that there are problems caused by desynchronisation between us
and Debian: for example as soon as Debian releases a bunch of
maintainers decide to remove backwards-compatibility on the grounds that
not many people are going to try to upgrade from etch directly to
squeeze, and this screws us over for LTS-to-LTS upgrades in some cases.
There's no magic bullet here; we just have to keep track of everything
and fix things up as best we can.

-- 
Colin Watson                                       [cjwatson at ubuntu.com]