Friday 27 September 2024

Re: Proposal to make MariaDB the default MySQL variant in Ubuntu 25.04

Hi Otto,

On Fri, Sep 27, 2024 at 09:59:46PM -0700, Otto Kekäläinen wrote:
> Hi!

> Should I maybe re-post this on some other mailing list or on
> https://discourse.ubuntu.com/?

Did you see this reply from Lena, which was waiting for input?

https://lists.ubuntu.com/archives/ubuntu-devel/2024-September/043133.html

> I did notice there was some people commenting the topic in the news
> article https://www.phoronix.com/news/Ubuntu-25.04-Maybe-MariaDB,
> which in turn was mentioned in
> https://discourse.ubuntu.com/t/ubuntu-weekly-newsletter-issue-858/48085).
> I was hoping some Ubuntu community members (in particular those who
> are not Canonical staff) would share some views here so we could see
> what is the general sentiment. Or has everyone but WordPress users
> fully migrated to PostgreSQL so that the topic of MySQL vs MariaDB is
> no longer of broad interest? ;-)
>
> On Thu, 19 Sept 2024 at 16:34, Otto Kekäläinen <otto@ubuntu.com> wrote:
> >
> > Hi Ubuntu devs,
> >
> > The MariaDB Server, a fork of MySQL created in response to it being
> > acquired by Oracle, has been the default MySQL variant in Debian since
> > 2016. Starting from Debian 9 "Stretch" in 2017, MariaDB has been the
> > only MySQL variant in stable Debian releases. The situation has been
> > similar in the Fedora and SuSE ecosystems — currently Ubuntu is the
> > only major Linux distribution that ships Oracle MySQL at all.
> >
> > I think it is now time for Ubuntu to follow suit and at least make
> > MariaDB the default in the Ubuntu 25.10 cycle, and potentially remove
> > MySQL in some later release.
> >
> > The 25.04 development cycle is not yet open, but I am submitting this
> > proposal now, as it would be an ideal time to plan and decide ahead,
> > and execute immediately at the start of the 25.04 dev cycle in early
> > November.
> >
> >
> > Benefits
> > =======
> >
> > The main benefits listed in order of importance:
> >
> > The MariaDB Server is more Ubuntu
> > ------------------------------------------------
> >
> > MariaDB is more compatible with the Ubuntu community values and closer
> > to the Ubuntu meaning "humanity to others" than Oracle MySQL. All Free
> > and Open Source Software proponents view MariaDB as a far better
> > option than Oracle MySQL, which only does code dumps at release to
> > stay GPL-compliant and has no openness beyond that. MySQL does accept
> > contributions, but under very strict contributor license terms and
> > without transparency on what happens with the submission, and their
> > contributor numbers are very low.
> >
> > While MariaDB isn't perfect, it does function far better in spirit
> > than Oracle, thanks to all MariaDB development happening in the open.
> > This means that anybody can see git commits in real-time, and
> > participate in all bug tracker, mailing list and chat discussions. To
> > mention some weaknesses, the reviews often take a long time and the CI
> > is not consistently green, but at least there are public code reviews
> > happening and all CI runs are public. This is in sharp contrast to how
> > Oracle runs MySQL development. Additionally, the MariaDB Server
> > development is stewarded by the non-profit MariaDB Foundation, with
> > two dozen sponsors to help guarantee continuity and openness [1].
> >
> >
> > The MariaDB Server is likely to outlive MySQL
> > -------------------------------------------------------------
> >
> > Oracle acquired Sun Microsystems in 2008, and MySQL with it. To avoid
> > antitrust lawsuits in the EU, Oracle made public commitments to not
> > kill MySQL, which at the time was considered a competitor to Oracle's
> > own database. While Oracle did sunset many other projects and thus
> > made room for a truly open version to live on (e.g. OpenOffice ⇾
> > LibreOffice, Hudson ⇾ Jenkins), in the case of MySQL, it has kept the
> > lights on for now. Some argue[2] however that Oracle has been slowly
> > killing MySQL in the past years by not adding relevant features to its
> > core GPLv2 edition, but instead putting all new cool things in
> > Heatwave, their closed source cloud-only offering.
> >
> > The MariaDB Server, on the other hand, has been steadily adding major
> > features. MariaDB offers for example the SQL_MODE=oracle mode to ease
> > migrations away from the Oracle database, something Oracle would never
> > do in MySQL as it would cannibalize their own main product. Supporting
> > users to migrate away from Oracle databases is important to advancing
> > open source adoption in general, and good for all current and future
> > Ubuntu users.
> >
> >
> > MariaDB is growing faster than MySQL
> > ----------------------------------------------------
> >
> > MySQL became the most popular open source database in the advent of
> > web applications in the late 1990s and in particular as part of the
> > LAMP stack. For example WordPress, Wikipedia and Facebook were
> > originally built on MySQL. However, in the past decade MySQL has been
> > in steady decline based on various data sources such as Google Trends,
> > Shodan Trends and DB-Engines. These data sources however show that
> > MariaDB has been steadily growing. The growth of MariaDB is far behind
> > the growth of PostgreSQL, but nevertheless MariaDB is growing faster
> > than MySQL.
> >
> > For several years already, the company behind WordPress, Automattic,
> > and the Wikimedia Foundation have been using MariaDB extensively and
> > have also been MariaDB Foundation sponsors. Most Linux distributions
> > have been shipping only MariaDB for nearly a decade. Ubuntu is one of
> > the few that has been resisting this trend, and I suggest it to be
> > changed now.
> >
> >
> > MariaDB is more stable
> > -------------------------------
> >
> > Both MySQL and MariaDB have bugs, and some (albeit a declining number)
> > of the bugs are identical, as they stem from the old code base that is
> > still the same for MySQL and MariaDB. However many users have noticed
> > that MySQL has in recent years had many severe bugs and the quality of
> > MySQL releases seems to have declined, in particular since MySQL
> > 8.0.29 [3]. The latest MySQL 8.0.38 has such a severe bug that Percona
> > publicly warns about upgrading to it [4].
> >
> > The stability of MariaDB is also directly visible in the Debian and
> > Ubuntu (Launchpad) bug trackers, where MariaDB has 55 and 2 bugs
> > compared to MySQL (8.0) with 150 and 38 bugs. Both variants are in
> > wide use and have had roughly the same number of releases, so the
> > numbers are mostly comparable. MariaDB has been getting stable
> > security updates on steady cadence since Ubuntu 14.04 in all LTS and
> > non-LTS versions and, to my recollection, with zero regressions.
> >
> >
> > MariaDB has more features
> > ------------------------------------
> >
> > MariaDB 11.7, scheduled to be announced for general availability in
> > February 2025, will have several features MySQL lacks. Notable
> > examples are full vector storage and search functionality for
> > retrieval augmented AI applications, complete year 2038 support,
> > online schema changes (ALTER TABLE without locking the entire table),
> > TLS enabled by default with zero-configuration certificate management,
> > new PARSEC authentication method for improved security and much more.
> > MySQL seems to be adding most new features to their non-open version,
> > while the open source version that Ubuntu uses hasn't seen that many
> > new significant features despite having a more frequent release
> > cadence now.
> >
> >
> > MariaDB is faster
> > -----------------------
> >
> > Speed has always been a selling point for MySQL/MariaDB compared to
> > other databases. For every new release of both MySQL and MariaDB, new
> > features are introduced, and they increase the overhead a bit.
> > However, MariaDB has a much better ratio of new features vs.
> > performance penalty, and MySQL has both fewer features and more
> > performance regressions [5]. Thus, users already on MySQL/MariaDB are
> > likely to value performance and likely would benefit from the 5-30%
> > performance improvement if switching to MariaDB (depends on workload).
> >
> >
> > Switching to MariaDB right now would be the optimal timing
> > ------------------------------------------------------------------------------
> >
> > Ubuntu 24.10 repositories currently contain MySQL 8.0, which will be
> > end-of-life in April 2026. Users will be faced with a decision to do
> > migration work from MySQL 8.0 to either a new major MySQL version or
> > to MariaDB. Due to MySQL aggressively deprecating features/SQL syntax,
> > upgrading to a new future MySQL version is likely going to require
> > extra work. Assuming MariaDB maintains its excellent backwards
> > compatibility track-record, upgrades to MariaDB from MySQL do not
> > require much application changes and is likely less disruptive to the
> > majority of users.
> >
> > Introducing MariaDB as the new default in Ubuntu 25.04 would ensure
> > that when Ubuntu 26.04 comes out, the migration path from MySQL 8.0 to
> > a future MariaDB version is as smooth as possible. This would also
> > help minimize the number of users who would run into issues upgrading
> > to MySQL 8.4 or 9.0 meanwhile.
> >
> >
> > Potential downsides and risks
> > =======================
> >
> > As stated above, MariaDB has been the default and only MySQL variant
> > in Debian for many years. All packages in Debian have thus been proven
> > to be fully MariaDB compatible for all practical purposes. No major
> > downside is to be expected, but any change has the potential to cause
> > disruptions and should be planned well ahead.
> >
> >
> > Unexpected Ubuntu-only MySQL dependencies
> > ---------------------------------------------------------------
> >
> > Changing the default MySQL variant from Oracle MySQL to MariaDB in
> > Ubuntu might lead to some unexpected breakage if Ubuntu has some
> > customizations regarding MySQL that are not present in Debian.
> >
> > To my knowledge there aren't any. Running `apt rdepends mysql*` on an
> > Ubuntu 24.10 host shows that the only packages that depend on
> > "mysql-server" specifically are "lyricue", which does not exist in
> > Debian at all, and "mylvmbackup", which hasn't had any new upstream
> > releases in a decade. All other hundreds of applications that depend
> > on MySQL depend on one of the `default-mysql-*` metapackages.
> >
> > Currently in Ubuntu, these `default-mysql-*` metapackages depend on
> > the actual MySQL packages. In Debian all the `default-mysql-*`
> > packages depend on equivalent MariaDB packages. Aligning Ubuntu with
> > Debian in this regard should go smoothly. All new installations would
> > start using MariaDB automatically, unless users specifically opt to
> > use MySQL.
> >
> >
> > Upgrade issues
> > ---------------------
> >
> > Changing the default MySQL variant by making the `default-mysql-*`
> > packages depend on equivalent MariaDB packages will not affect
> > existing systems and they will continue to run the current MySQL
> > server they already have.
> >
> > If a host is running Ubuntu 16.04 or 18.04 with MySQL 5.7 a user could
> > choose to upgrade directly to MariaDB by simply issuing `apt install
> > mariadb-server`.
> >
> > If a host is running Ubuntu 20.04 or newer and has MySQL 8.0, the
> > in-place upgrade to MariaDB is not possible with a single apt command.
> > Those users could however be instructed to do a logical dump as a SQL
> > file with the mysqldump tool, and uninstall MySQL 8.0, install the
> > latest MariaDB and import the SQL file.
> >
> > If users do nothing, they would stay on MySQL 8.0 and not have to
> > consider anything until MySQL 8.0 is end-of-life in April 2026. At
> > that point users could do the manual upgrade via dump-and-restore to
> > MariaDB.
> >
> > Note that while MySQL to MySQL upgrades seem smaller in name than
> > MySQL to MariaDB upgrades, newer MySQL versions have deprecated a
> > bunch of features and SQL syntax. Thus, upgrades to new MySQL versions
> > may require more application changes to be done than simply upgrading
> > to MariaDB, which so far has an excellent track-record of backwards
> > compatibility.
> >
> > There are configuration options that are incompatible between MySQL
> > and MariaDB. There are ongoing efforts to provide a migration tool
> > [6]. With more user feedback, this process can be better polished for
> > Ubuntu 26.04 LTS.
> >
> >
> > Cross-host compatibility
> > -------------------------------
> >
> > Users who have multiple Ubuntu hosts running MySQL servers and
> > applications using them could in theory face some issues. For example,
> > when an application server is upgraded to use the MariaDB client while
> > the database server continues to run a MySQL server. However, the
> > MySQL wire protocol has not had any changes in decades and thus the
> > MySQL and MariaDB client libraries and client binaries are fully
> > interoperable: one can use a MariaDB client to connect to a MySQL
> > database and vice versa.
> >
> > The exception to this is any client using the MySQL X protocol. That
> > is not supported in MariaDB. Those users can however choose to
> > continue using MySQL. This proposal is not suggesting removing MySQL
> > from Ubuntu, but simply to make MariaDB the default for a better
> > future path.
> >
> > Another consideration is connector libraries, for example for Python
> > or Java. Due to the protocol compatibility and shared background, most
> > MySQL connectors are compatible with MariaDB. There are some
> > incompatibilities in package names in the MariaDB Python connector,
> > but these can be worked around. Thanks to having had MariaDB as
> > default in Debian for several years, the remaining issues are
> > marginal, but not zero.
> >
> > A third consideration is replication setups. Ubuntu does not include
> > any replication automation, so all replication setups are managed
> > manually or by 3rd party automation software. Users would need to be
> > instructed to upgrade all replicas first, as MySQL and MariaDB in
> > general are designed to allow replicas to connect to old sources.
> > After upgrading the replica, users could then promote it to be the
> > primary source instance, and shut down the old primary to complete the
> > upgrade process.
> >
> > While there are some known edge cases when upgrades from MySQL to
> > MariaDB do not fully work, they are in practice rare. Considering that
> > all of Debian upgraded smoothly to MariaDB, and that ever since
> > MariaDB has been steadily adding features that smoothen the migration
> > path, the upgrade from MySQL to MariaDB should for most users work
> > flawlessly.
> >
> >
> > Canonical product impact
> > ----------------------------------
> >
> > As Canonical is the main sponsor of Ubuntu, the change needs to also
> > have some consideration for Canonical's business needs. Currently
> > Canonical advertises MySQL at https://canonical.com/data/mysql but
> > there is no https://canonical.com/data/mariadb, and Canonical's
> > automation offering https://charmhub.io/mysql seems to be focused on
> > MySQL. Kubernetes operators, OpenStack modules and alike exist for
> > MariaDB, so it is not a technical limitation, but some effort would be
> > needed to productize MariaDB automation.
> >
> >
> > Users may need education about the change
> > -----------------------------------------------------------
> >
> > There might still be many users who have not heard about MariaDB and
> > do not know that their current app using MySQL as the backend can
> > actually run equally well (and in some cases better and faster) on
> > MariaDB. This can however be mitigated by explaining this in release
> > notes and in documentation, like has been done in other migrations
> > (e.g. OpenOffice to LibreOffice, or Oracle Java to OpenJDK).
> >
> > Small pun: The fact that Ubuntu 24.10 is code name "Oracular" will
> > make it easier for users to remember it was the last Ubuntu version
> > that defaulted to Oracle MySQL.
> >
> >
> > Alternative considerations
> > ====================
> >
> > While I propose MariaDB Server as the best option, for a holistic
> > assessment readers should also consider alternative solutions or
> > mitigations to the problems faced by Oracle MySQL.
> >
> >
> > Keep MySQL, but demand more openness
> > ---------------------------------------------------------
> >
> > If the Ubuntu community wants to stick to MySQL, but make it less
> > risky, Ubuntu should seek ways to promote or protect the openness of
> > MySQL which is currently nearly non-existent. Ubuntu could perhaps use
> > its large community to persuade MySQL to publish git commits in
> > real-time and allow participation in the MySQL development, and the
> > Ubuntu community could promote every last bit of independent MySQL
> > community activity that still exists (e.g. promote
> > https://planet.oursqlcommunity.org/).
> >
> >
> > Percona Server
> > ---------------------------------------------------------
> >
> > If the Ubuntu community wakes up to the situation with Oracle MySQL,
> > but does for some reason not want to switch to MariaDB, another
> > alternative would be to collaborate with Percona. Ubuntu could
> > consider offering the Percona Server, which is a fork of MySQL that
> > follows Oracle more closely, but with added stability and more
> > features. To illustrate the situation with one example, the audit
> > plugin that Oracle MySQL only offers in their closed-source edition is
> > available as open source both in the MariaDB Server and Percona
> > Server. There is however added risk about the unknown capability of
> > Percona Server truly maintaining a proper fork, given the age,
> > complexity, depth and breadth of MySQL as a project.
> >
> >
> > References
> > =========
> >
> > [1] https://mariadb.org/
> > [2] https://www.percona.com/blog/is-oracle-finally-killing-mysql/
> > [3] https://jfg-mysql.blogspot.com/2023/11/thoughts-on-october-2023-mysql-releases.html
> > [4] https://www.percona.com/blog/do-not-upgrade-to-any-version-of-mysql-after-8-0-37/,
> > https://www.percona.com/blog/mysql-8-0-vs-5-7-are-the-newer-versions-more-problematic/
> > [5] https://smalldatum.blogspot.com/2024/04/sysbench-on-less-small-server-mariadb.html
> > [6] https://github.com/MariaDB/server/pull/2976
> >
> >
> > Package trackers
> > =============
> > https://tracker.debian.org/pkg/mariadb
> > https://launchpad.net/ubuntu/+source/mariadb
> >
> > https://tracker.debian.org/pkg/mysql-8.0
> > https://launchpad.net/ubuntu/+source/mysql-8.0
> >
> > https://tracker.debian.org/pkg/mysql-defaults
> > https://launchpad.net/ubuntu/+source/mysql-defaults
> >
> >
> > Technical details about MariaDB release policies and testing
> > =============================================
> >
> > The MariaDB yearly LTS model in February provides the opportunity for
> > a MariaDB LTS release to correspond to the LTS cycle of Ubuntu. The
> > to-be-LTS version should be available as a release candidate in
> > November 2025 at the start of the Ubuntu 26.04 LTS dev cycle:
> > https://mariadb.com/kb/en/mariadb-release-model/
> >
> > The upstream MariaDB developers test against the architectures of
> > amd64, arm64, s390x and ppc64le against real hardware of Ubuntu LTS
> > releases well in advance to their release:
> > https://buildbot.mariadb.org/#/grid?branch=11.4
> >
> > MariaDB is well tested on Ubuntu already, thanks to the official
> > Docker container images being built on the latest Ubuntu LTS tag,
> > which has well over a billion total image pulls:
> > https://hub.docker.com/_/mariadb
> >
> >
> >
> > Disclaimer
> > ========
> > I am the maintainer for MariaDB in both Debian and Ubuntu, and
> > distrust and detest Oracle as a company, so I am naturally biased
> > towards MariaDB. I am however striving to represent both balanced pros
> > and cons in this proposal and including references.
>
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