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> to reduce the impact of a change. From my original reply:
>
> > If there's a high maintenance cost, we haven't properly identified the
> optimal way to separate functionality between tripleo/quickstart.
>
> IMHO this is a side effect of having a whole bunch of roles in a
> single repo.  oooq-extras has a mix of tripleo and non-tripleo related
> content. The reproducer IMHO is related to provisioning and could fall
> in the oooq repo and not oooq-extras.  This is a structure problem
> with quickstart.  If it's not version specific, then don't put it in a
> version specific repo. But that doesn't mean don't use version
> specific repos at all.
>
> This is one of the reasons why we're opting not to use this pattern of
> a bunch of roles in a single repo for tripleo itself[0][1][2].  We
> learned with the puppet modules that carrying all this stuff in a
> single repo has a huge maintenance cost and if you split them out you
> can identify re-usability and establish proper patterns for moving
> functionality into a shared place[3].  Yes there is a maintenance cost
> of maintaining independent repos, but at the same time there's a
> benefit of re-usability by other projects/groups when you expose
> important pieces of functionality as a standalone. You can establish
> clear ways to interact with each piece, test items, and release
> independently.  For example the ansible-role-container-registry is not
> tripleo specific and anyone looking to manage a standalone docker
> registry can use it & contribute.
>
>
We were moving between having all roles in one repo and having a separate
repo for each role a few times. Each case has it's advantages and
disadvantages. Last time we moved to have roles in 2 repos - quickstart and
extras, it was a year ago I think. So far IMHO it's the best approach.
There will be a mechanism to install additional roles, like we have for
tirpleo-upgrade, ops-tools, etc etc.
It may be a much broader topic to discuss, although I think having part of
roles branched and part of not branched is much more headache.
Tripleo-upgrade is a good example of it.


> > So in 90% code we DO need to backport every change, take for example the
> > latest patch to extras: https://review.openstack.org/#/c/570167/, it's
> > fixing reproducer. If oooq-extra was branched, we would need to backport
> > this fix to every and every branch. And the same for all other 90% of
> code,
> > which is complete nonsense.
> > Just because not using "{% if release %}" construct - to block the whole
> > work of CI team and make the CI code is absolutely unmaintainable?
> >
>
> And you're saying what we currently have is maintainable?  We keep
> breaking ourselves, there's big gaps in coverage and it takes
> time[4][5] to identify breakages. I don't consider that maintainable
> because this is a recurring topic because we clearly haven't fixed it
> with the current setup.  It's time to re-evaluate what we have an see
> if there's room for improvement.  I know I wasn't proposing to branch
> all the repositories, but it might make sense to figure out if there's
> a way to reduce our recurring issues with stable branches or
> independent modules for some of the functions in CI.
>

Considering this is how we broke Queens, I'm not sure I agree.
>
>
First of all I don't see any connection between maintenance and CI
breakages, it's different topics. And yes, it IS maintainable CI that we
have now, and I have what to compare it with. I remember very well
tripleo.sh based approach, also you can see almost green dashboards last
time which proves my statement. CI is not ideal now, but it's definitely
much better than 1-2 years ago.

Of course we have breakages, the CI is actually history of breakages and
fixes, as any other product. Wrt queens issue, it took about a week to
solve it not because it was so hard, but because we had a very difficult
weeks when trying to fix all Centos 7.5 issues and queens branch was in
second priority. And by the way, we fixed everything much faster then it
was with CentOS 7.4.  Having the negative attitude that every CI breakage
is proof of wrong CI structure is not correct and doesn't help. If
branching helped in this case, it would create much bigger problems in all
other cases.

Anyway, we saw that having branch jobs in OVB only didn't catch queens
issue (why - you know better) so we added multinode branch specific ones,
which will catch such issues in the future. We hit the problem, solved it,
set preventive actions and are ready to catch it next time. This is a
normal CI workflow and I don't see any problem with it. Having multinode
branch jobs is actually pretty similar to "branching" repos but without
maintenance nightmare.

Thanks

Thanks,
> -Alex
>
> [0] http://git.openstack.org/cgit/openstack/ansible-role-
> container-registry/
> [1] http://git.openstack.org/cgit/openstack/ansible-role-redhat-
> subscription/
> [2] http://git.openstack.org/cgit/openstack/ansible-role-tripleo-keystone/
> [3] http://git.openstack.org/cgit/openstack/puppet-openstacklib/
> [4] https://review.openstack.org/#/c/565856/
> [5] https://review.openstack.org/#/c/569830
>
> > Thanks
> >
> >
> >
> > On Wed, May 23, 2018 at 7:04 PM, Alex Schultz <aschultz at redhat.com>
> wrote:
> >>
> >> On Wed, May 23, 2018 at 8:30 AM, Sagi Shnaidman <sshnaidm at redhat.com>
> >> wrote:
> >> > Hi, Sergii
> >> >
> >> > thanks for the question. It's not first time that this topic is raised
> >> > and
> >> > from first view it could seem that branching would help to that sort
> of
> >> > issues.
> >> >
> >> > Although it's not the case. Tripleo-quickstart(-extras) is part of CI
> >> > code,
> >> > as well as tripleo-ci repo which have never been branched. The reason
> >> > for
> >> > that is relative small impact on CI code from product branching. Think
> >> > about
> >> > backport almost *every* patch to oooq and extras to all supported
> >> > branches,
> >> > down to newton at least. This will be a really *huge* price and non
> >> > reasonable work. Just think about active maintenance of 3-4 versions
> of
> >> > CI
> >> > code in each of 3 repositories. It will take all time of CI team with
> >> > almost
> >> > zero value of this work.
> >> >
> >>
> >> So I'm not sure I completely agree with this assessment as there is a
> >> price paid for every {%if release in [...]%} that we have to carry in
> >> oooq{,-extras}.  These go away if we branch because we don't have to
> >> worry about breaking previous releases or current release (which may
> >> or may not actually have CI results).
> >>
> >> > What regards patch you listed, we would have backport this change to
> >> > *every*
> >> > branch, and it wouldn't really help to avoid the issue. The source of
> >> > problem is not branchless repo here.
> >> >
> >>
> >> No we shouldn't be backporting every change.  The logic in oooq-extras
> >> should be version specific and if we're changing an interface in
> >> tripleo in a breaking fashion we're doing it wrong in tripleo. If
> >> we're backporting things to work around tripleo issues, we're doing it
> >> wrong in quickstart.
> >>
> >> > Regarding catching such issues and Bogdans point, that's right we
> added
> >> > a
> >> > few jobs to catch such issues in the future and prevent breakages,
> and a
> >> > few
> >> > running jobs is reasonable price to keep configuration working in all
> >> > branches. Comparing to maintenance nightmare with branches of CI code,
> >> > it's
> >> > really a *zero* price.
> >> >
> >>
> >> Nothing is free. If there's a high maintenance cost, we haven't
> >> properly identified the optimal way to separate functionality between
> >> tripleo/quickstart.  I have repeatedly said that the provisioning
> >> parts of quickstart should be separate because those aren't tied to a
> >> tripleo version and this along with the scenario configs should be the
> >> only unbranched repo we have. Any roles related to how to
> >> configure/work with tripleo should be branched and tied to a stable
> >> branch of tripleo. This would actually be beneficial for tripleo as
> >> well because then we can see when we are introducing backwards
> >> incompatible changes.
> >>
> >> Thanks,
> >> -Alex
> >>
> >> > Thanks
> >> >
> >> >
> >> > On Wed, May 23, 2018 at 3:43 PM, Sergii Golovatiuk <
> sgolovat at redhat.com>
> >> > wrote:
> >> >>
> >> >> Hi,
> >> >>
> >> >> Looking at [1], I am thinking about the price we paid for not
> >> >> branching tripleo-quickstart. Can we discuss the options to prevent
> >> >> the issues such as [1]? Thank you in advance.
> >> >>
> >> >> [1] https://review.openstack.org/#/c/569830/4
> >> >>
> >> >> --
> >> >> Best Regards,
> >> >> Sergii Golovatiuk
> >> >>
> >> >>
> >> >> ____________________________________________________________
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> >> >
> >> >
> >> >
> >> >
> >> > --
> >> > Best regards
> >> > Sagi Shnaidman
> >> >
> >> >
> >> > ____________________________________________________________
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> >>
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> >
> >
> > --
> > Best regards
> > Sagi Shnaidman
> >
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-- 
Best regards
Sagi Shnaidman
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