On 11/17/2016 07:26 PM, Adam Williamson wrote:
Hi, folks!
While looking into an issue with how GNOME Software decides which
release to offer an upgrade to when there's more than one plausible
candidate, I noticed something interesting: we do not actually have a
policy on what we 'recommend' people to do in this case.
There's one specifically planned-for (I'm trying hard to avoid using the
word 'supported' here) case where a Fedora user may want to upgrade
across two release versions at once. It's why we do the release cycle
'overlap', where the N-2 release is maintained for a month after the N
release goes stable: we specifically want to allow people not to have to
upgrade every single release, but allow them to upgrade every other
release instead.
That is, we're generally on record as thinking it's OK to go 23 -> 25 ->
27 -> 29 etc., so long as you do the upgrade within a month of the new
release coming out each time.
However, if you look at our official instructions on upgrading:
https://fedoraproject.org/wiki/Upgrading
https://fedoraproject.org/wiki/DNF_system_upgrade
https://docs.fedoraproject.org/en-US/Fedora/24/html/Installation_Guide/ch...
(that one just links to the wiki page)
You'll notice we don't explicitly specify *how* you should do this. That
is, if you're currently running Fedora 23, and you want to upgrade to
Fedora 25 next week, are you supposed to:
i) Upgrade to Fedora 24 first, then from Fedora 24 to Fedora 25
ii) Upgrade directly to Fedora 25
It's hard for us to request specific behaviour from gnome-software when
we don't actually know which approach we as a distribution recommend :)
A couple of releases ago, direct N+2 upgrades were written into the
release criteria, which now read:
"For each one of the release-blocking package sets, it must be possible
to successfully complete a direct upgrade from fully updated
installations of the last two stable Fedora releases with that package
set installed."
openQA tests direct N+2 upgrades of Workstation, KDE, Server and minimal
package sets.
This is obviously indicative, but still, it only considers clean
installs of the release-blocking package sets. In the real world, people
upgrade with much messier package sets.
As another data point, while updating the 'upgrading with bare dnf' (not
dnf-system-upgrade) instructions a couple of weeks back, I noticed those
instructions recommended the 'upgrade one release at a time' strategy.
So, I guess the questions here are:
1) Which of the two should be our 'officially recommended' approach?
2) Should we also say the other one is OK but just less-recommended, or
specifically discourage it?
OK, so we have two cases here:
1) gnome-software as is currently in F23 and F24
2) gnome-software future releases
For (1), the version of gnome-software in F23 and F24 currently doesn't
have the UI in place to allow choosing which version to upgrade to, so
gnome-software needs to somehow automatically pick the version. My idea
here was patch F23 and F24 gnome-softwares so that they always offer the
latest non-development version, bounding it to N+2.
Example: A user has F23 installed. F24 comes out. gnome-software offers
to upgrade to F24. 6 months later F25 comes out, gnome-software switches
to offering a F23 to F25 upgrade. 3 years later when F23 and F25 are
both EOL, F23 gnome-software still continues to offer the F25 upgrade.
As for (2), I guess we should do the same as (1) but just allow the user
to choose the N+1 release as well in addition to N+2.
--
Kalev