From 4cd1fc03ec10aa73eceb01c60ee2c173e885abe6 Mon Sep 17 00:00:00 2001 From: Matt Riedemann Date: Thu, 1 Mar 2018 06:04:52 -0500 Subject: [PATCH] Add a resolution about stable branch EOL and "extended maintenance" We've talked about this for years, and talked some more at the Rocky PTG. This adds a resolution to try and document / summarize the outcomes of the Sydney summit and Rocky PTG. Change-Id: I94b0421d8a489026300789b61b0293dd2e61726d --- doc/source/conf.py | 1 + resolutions/20180301-stable-branch-eol.rst | 144 +++++++++++++++++++++ 2 files changed, 145 insertions(+) create mode 100644 resolutions/20180301-stable-branch-eol.rst diff --git a/doc/source/conf.py b/doc/source/conf.py index 6bb915e85..8552d81c2 100644 --- a/doc/source/conf.py +++ b/doc/source/conf.py @@ -30,6 +30,7 @@ sys.path.insert(0, os.path.join(os.path.abspath('.'), '_exts')) # coming with Sphinx (named 'sphinx.ext.*') or your custom ones. extensions = [ 'sphinx.ext.extlinks', + 'sphinx.ext.todo', 'atcs', 'members', 'projects', diff --git a/resolutions/20180301-stable-branch-eol.rst b/resolutions/20180301-stable-branch-eol.rst new file mode 100644 index 000000000..6c053190d --- /dev/null +++ b/resolutions/20180301-stable-branch-eol.rst @@ -0,0 +1,144 @@ +=================================================== +2018-03-01 Extended maintenance for stable branches +=================================================== + +The OpenStack `stable branch maintenance team`_, among other teams such as +`QA`_, `infra`_, `vulnerability management team (VMT)`_, the `release team`_, +alongside users, operators, vendors and distributions, have talked for years +about extending the life of the stable branches. + +There was a cross-project discussion about this during the Newton summit: + +https://etherpad.openstack.org/p/stable-branch-eol-policy-newton + +And another at the Queens summit: + +https://etherpad.openstack.org/p/SYD-forum-upstream-lts-releases + +There have been discussions about stable branch end of life, release process, +long-term support releases, etc, at every face-to-face event (PTG, summit) +for years. + +This resolution does not intend to cover all of the history, viewpoints, +use cases, caveats, etc - it would never end. The purpose of this resolution +is to summarize and state the stance of the various upstream stable branch +maintainers and related teams (mentioned above) with respect to extended +maintenance windows for stable branches and their end of life process. + +The first branch this will apply to is stable/ocata. + +End of life +----------- + +The stable branches shall remain open to accept fixes as long as reasonably +possible. Codifying when a branch can no longer be maintained is not within +the scope of this resolution, but it typically means no one is maintaining +the branch, it is not tested and fixes cannot merge. + +The current end of life process of applying the ``-eol`` +tag and deleting the branch, cleaning up related infra scripts, etc, will +change to not delete the branch. Instead, a ``-em`` tag will be +applied on the final release indicating the branch is now in +*extended maintenance (EM)* mode. + +If at some point fixes cannot land in a given project and there is no +reasonable solution, then the branch will need to be EOL for that project. +Note that it is possible for our CI infrastructure to `function based on EOL +tags`_. + +Releases +-------- + +The upstream stable branch maintenance team shall maintain and release each +branch for typically 18 months, which has been the historical lifespan of a +branch in OpenStack. After that, there will be no releases as a release +would indicate the same level of support from the upstream teams, which may +not be the case. Contributors can continue to push fixes and they can be +merged but they will not be released upstream. + +Keep in mind that the overarching goal of this resolution is to provide a +common place (and infrastructure) for deployers, contributors and vendors +to share and get fixes for older branches. It is not to indefinitely extend +the same level of upstream support for all branches for all time. + +Support phases +-------------- + +The traditional `support phases`_ may change as a result of this resolution +but the details are out of scope for this document, and any changes would be +part of the stable branch guidelines documentation. + +Note that the traditional **Phase III** for stable branch maintenance may be +dropped since its purpose was mostly to highly restrict applicable fixes to a +branch that will soon be end of life. In other words, teams must take extra +care to not backport regressions to a branch before it is EOL and then +cannot be fixed upstream. + +With the removal of EOL after 18 months, the need for Phase III type +restrictions is severely reduced to the point of no longer being necessary. + +.. note:: VMT coverage for EM branches would be on a best-effort basis due + to the confidence of the VMT being able to research a + vulnerability's presence in very old EM branches or that + backported security fixes to said branches actually address the + vulnerability there. + +Core teams +---------- + +The stable branch core teams will remain unchanged between EM and non-EM +branches. If people are doing good work on the EM stable branches, then +they likely should be included in the regular stable branch core team for +the project. + +Testing +------- + +The EM branches will continue to run the same level of CI testing after +the standard 18 month window, as long as feasible. + +Tempest is branchless and has historically dropped support for testing +older branches once they are end of life. This allows Tempest (and devstack) +to drop compatibility code and other technical debt. + +Once a branch enters extended maintenance mode, the QA team *may* move +forward with changes that disrupt an old branch if those changes cannot be +easily made another way. This resolution will not attempt to predict or +codify what those types of changes might be, or how maintenance on older +branches can be extended and still run integration tests with Tempest. The +point is the QA team can move forward and not be hindered by the extended +maintenance of the stable branches. + +In other words, these older branches might, at some point, just be running +pep8 and unit tests but those are required at a minimum. + +Appropriate fixes +----------------- + +Backports to these branches must follow the upstream +`stable branch maintenance guide`_. This includes but is not limited to: + +* Bug fixes only. Features will not be accepted on stable branches. +* Backports must go in order from the newest branch where the bug exists. + This means if a bug is to be fixed in Ocata, it must also be fixed first + in Pike, and Queens before Pike, Rocky before Queens, etc. Fixes cannot + skip branches lest people would upgrade and be regressed. +* Project teams should not block proposed fixes for a branch based on the + non-technical merit of the proposed branch. +* Following on the last point, projects teams will not pick and choose EM + branches. For example, a project shall not say that Ocata and Queens can + have extended maintenance but Pike will not. + +It is worth noting that the stable branch maintenance guide provides +guidelines for appropriate fixes, but each backport should be judged on its +own by the core team based on relative risk versus severity of the bug being +fixed. + +.. _stable branch maintenance team: https://governance.openstack.org/tc/reference/projects/stable-branch-maintenance.html +.. _QA: https://governance.openstack.org/tc/reference/projects/quality-assurance.html +.. _infra: https://governance.openstack.org/tc/reference/projects/infrastructure.html +.. _vulnerability management team (VMT): https://docs.openstack.org/project-team-guide/vulnerability-management.html +.. _release team: https://governance.openstack.org/tc/reference/projects/release-management.html +.. _function based on EOL tags: https://review.openstack.org/#/c/520095/ +.. _support phases: https://docs.openstack.org/project-team-guide/stable-branches.html#support-phases +.. _stable branch maintenance guide: https://docs.openstack.org/project-team-guide/stable-branches.html#appropriate-fixes \ No newline at end of file