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F40 MariaDB & MySQL repackaging

This is a proposed Change for Fedora Linux.
This document represents a proposed Change. As part of the Changes process, proposals are publicly announced in order to receive community feedback. This proposal will only be implemented if approved by the Fedora Engineering Steering Committee.

Summary

A bigger set of smaller changes for which I want to extend visibility:

  • Drop i686 arches
  • Rename package 'community-mysql' to 'mysql' and Stop providing 'mysql' symbols by package 'mariadb'
  • Drop cross-installation functionality
  • Switch to the versioned layout of MariaDB and MySQL packages
  • Introduce MariaDB 10.11 and MySQL 8.1

Owner

Current status

  • [<will be assigned by the Wrangler> devel thread]
  • FESCo issue: <will be assigned by the Wrangler>
  • Tracker bug: <will be assigned by the Wrangler>
  • Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

Most (if not all) of the changes I propose here doesn't probabbly need such a formal process as Fedora Change is. What I want is primarly to increase the visibility of the changes, and preserve those information in a permament document, allowing both users and maintainers to find this page both now, and in the future.



Drop of the i686 architecture:

Both MariaDB and MySQL databases are huge pieces of software, taking hours to compile and test, taking up noticeable amount of system resources on our builders and any attached system (e.g. repositories). At the same time, I can hardly imagine anyone running those databases in production on i686 nowadays. I will keep i686 variant for the client library, the 'libmariadb.so', which can be found in the 'mariadb-connector-c' package. However the DB servers themselves are IMO expendable.

On top of the resources saved, I also keep finding bugs and issues, that are exclusive for the i686 architecture. They are more often than not in the tooling around, rather than the package itself, but it keeps needlessly devouring my time and energy anyway.

Last but not least, all maintainers are currently encouraged to drop i686 support, starting from leaf packages.
https://fedoraproject.org/wiki/Changes/EncourageI686LeafRemoval

So I have to make sure the MariaDB and MySQL are leaf package on i686 architecture, so I can drop them on i686 too.
I've started the process by fixing https://bugzilla.redhat.com/show_bug.cgi?id=2241091


I use the following code to find out which packages requires which provides: 

 #!/bin/bash
 mkdir -p RESULTS
 for REPO in "rawhide" "rpmfusion-free" "rpmfusion-nonfree" ; do
   for PROVIDE in "mariadb" "mariadb-devel" "mariadb-connector-c" "mariadb-connector-c-devel" "pkgconfig(mariadb)" "pkgconfig(libmariadb)" "mysql" "mysql-devel" "community-mysql" "community-mysql-devel" "pkgconfig(mysql)" ; do
     echo -e "\n\nREPO: $REPO ; PROVIDE: $PROVIDE";
     dnf -q --repo="$REPO" --repo="$REPO"-source repoquery --whatrequires "$PROVIDE" --alldeps | tee "./RESULTS/$REPO-$PROVIDE"
   done
 done

It show that other than the last few occurrences described in the bugzilla above, all is ready.



Rename package 'community-mysql' to 'mysql'
and Stop providing 'mysql' symbols by package 'mariadb':

When MariaDB was introduced to Fedora, it seemed like it eventually replaces MySQL and therefore the packages were designed so that 'mysql' names were provided by MariaDB and MySQL was renamed to community-mysql.

The both projects were drop-in replacements at that time, so that design helped the smooth transition. Since then, a lot changed. First, those two databases developed different sets of features. The last "major major" version of MariaDB marked as a drop-in replacement is MariaDB 5.5. From MariaDB 10.0, it is usually still easy to upgrade from one to another.
https://mariadb.com/kb/en/mariadb-vs-mysql-compatibility/

Since MySQL 8.0 and circa MariaDB 10.5, the differences grew significantly and so it does not make sense anymore to provide 'mysql' names by MariaDB package(s).

Moreover, the package name 'community-mysql' is Fedora specific. Oracle upstream uses 'mysql-community', Debian, RHEL and CentOS Stream use 'mysql'. From experience I can say users usually search for 'mysql' name. To keep the naming convention closer to Fedora-related clones, the proposal is to rename the MySQL packages from 'community-mysql' to 'mysql'.

This change will save me, the maintainer, noticeable amount of time and energy when cherry-picking commits and patches from Fedora to CentOS Stream and RHEL.
And the more energy I save downstream, the more I can put into Fedora and upstream.

This change was being prepared to be proposed back for Fedora 37, but we left it unfinished due to capacity reasons: https://fedoraproject.org/wiki/Changes/MariaDB_MySQL_Renaming



Drop cross-installation functionality:

In Fedora, I currently allow, on the packaging level, to cross install server of one DB with client of another.
Specifically, you can install MariaDB server with MySQL client or MySQL server with MariaDB client.

I introduced this functinality to try it out, in hope of delivering a handy enhancement for the users.
Sadly, the drawbacks outweights the positives. This behavior become a generator of elusive bugs I was never able to resolve.
E.g.: https://bugzilla.redhat.com/show_bug.cgi?id=2026933

Moreover, as the MariaDB and MySQL projects diverged significantly (see the above point), it stopped to make sense around the time the MariaDB stopped to be drop-in replacement for MySQL.

AFAIK, Fedora is the only distribution I know of, which ever allowed such installation combination.
I though it would be interesting, I tried it, I found out, now I want to end the experiment.



Switch to the versioned layout of MariaDB and MySQL packages:

I used the modularity heavily, as a package maintainer.
It allowed me to ship alternative versions of MariaDB that I or the users wanted. During chnages of the default major version of MariaDB in Fedora, they served as a handy way for anyone to use them way before the change is implemented, or after it when the haven't adapted their systems to the new default version. I've regurarly selected the versions I maintain in CentOS Stream and RHEL - those which received the most care - and supported them fro the longest time as Fedora modules.

With Modularity retired https://fedoraproject.org/wiki/Changes/RetireModularity I have lost this ability.

When researching alternative approaches, only one seem to cover my goals without too much of additional fuss.
That are the "Multiple packages with the same base name":
https://docs.fedoraproject.org/en-US/packaging-guidelines/Naming/#multiple

I want to change the packaging structure so the result will look as follows:

  • The unversioned name ('mariadb') will become a meta-package
    • It will point to the one versioned variant which I choose to be the default one for the given Fedora release
    • It will provide all of the unversioned names for the versioned variant that is default for the given Fedora release, to minimize the changes visible to the users
  • All other versions will have their own versoined package (e.g "mariadb10.5" "mariadb10.11") and will conflict with each other

This will allow for:

  • users to keep using the unversioned names they are used to
  • mainatiner to change the default version for a given Fedora release on a single, centralized place
  • users to enjoy all of the features of the modularity I offered them, in a simpler way
  • maintainer to add new versions quickly, without any need of changing the default version (other than adding new conflicts)
 Note:
 I specifically don't want the packages to be parallel installable. I only want them to be parallel available.
 That's why I didn't choose "Alternatives" as the solution:
 https://docs.fedoraproject.org/en-US/packaging-guidelines/Alternatives/



Introduce MariaDB 10.11 and MySQL 8.1

I would like to introduce MariaDB 10.11 and MySQL 8.1 into the Fedora.

Based on the previous point, it should be achieved without any user disturbance, as I won't change what is the default version in the distribution, I will just add an alternative for the users to choose from.

Proof of concept (needs additional work) for MariaDB 10.11 here:
https://koji.fedoraproject.org/koji/taskinfo?taskID=102927697
https://src.fedoraproject.org/fork/mschorm/rpms/mariadb/commits/10.11-LTS


Feedback

None received yet (02/10/2023)


Benefit to Fedora

Drop i686 arches

  • Maintainer regaining time and energy, when I stop dealing with i686 specific bugs
  • Fedora infrastructure regaining the system resources needed to be put into hours long compilations, storage, etc.
  • Also 'BuildRequires:' regarding MariaDB and MySQL will get fixed across the packages

Rename package 'community-mysql' to 'mysql' and Stop providing 'mysql' symbols by package 'mariadb'

  • Aligning with other distributions
  • Recognizing the differences between MariaDB and MySQL that grew over time
  • Maintainer regaining some time and energy from downstream work

Drop cross-installation functionality

  • Elusive bugs caused by this will vanish, maintainer doesn't need to deal with them
  • Recognizing the differences between MariaDB and MySQL that grew over time

Switch to the versioned layout of MariaDB and MySQL packages

  • Allows to regain all of the functinality lost after Modularity retirement
    • Helps maintainer to avoid the painful decision which single version of the DB to pack into Fedora
    • Helps with upgrades of the default version - users may choose to upgrade earlier, or later

Introduce MariaDB 10.11 and MySQL 8.1

  • New stuff that users wait for, yay \o/ !


Scope

  • Proposal owners:
    • request several repositories to be created
    • may need to go through a package review process several times (ufortunatelly)
  • Other developers:
    • ~6 remaining package(r)s to accept the PRs regarding usage of correct "BuildRequires:" or fix their packages in other way accordingly, in order to accomplish the i686 drop.
  • Policies and guidelines: N/A (not needed for this Change)
    • Should the Guidelines be in conflict with a reasonable approach I propose regarding the versioned packages, lowering their MUST to SHOULD in certain cases or getting FeSCo exception.
  • Trademark approval: N/A (not needed for this Change)
  • Alignment with Community Initiatives:


Upgrade/compatibility impact

Drop i686 arches

  • Users relying on i686 build of the database servers don't have any upgrade path

Rename package 'community-mysql' to 'mysql' and Stop providing 'mysql' symbols by package 'mariadb'

  • The package 'mariadb' will no longer be installed prefferably instead of package 'mysql' when doing "dnf install mysql" (and other subpackages)

Drop cross-installation functionality

  • Users relying on this atypical setup don't have any clear upgrade path
    • Such cases should only happen on depelopment setups, which is solvable with containers or simmilar semi-isolation

Switch to the versioned layout of MariaDB and MySQL packages

  • Nothing I can think of

Introduce MariaDB 10.11 and MySQL 8.1

  • Nothing I can think of


How To Test

Drop i686 arches

  • i686 doesn't exist anymore

Rename package 'community-mysql' to 'mysql' and Stop providing 'mysql' symbols by package 'mariadb'

  • The package 'mariadb' will no longer be installed prefferably instead of package 'mysql' when doing "dnf install mysql" (and other subpackages)
  • Using names 'mariadb' and 'community-mysql' leads to the same results as before

Drop cross-installation functionality

  • Cross-installation not allowed anymore

Switch to the versioned layout of MariaDB and MySQL packages

  • Test updates, upgrades, reinstalls, etc.
    • Users should get the same functional results as before with the same names as before, while having differently named packages present on the system

Introduce MariaDB 10.11 and MySQL 8.1

  • Test upgrades / downgrades between versions


User Experience

Drop i686 arches

  • i686 functionality lost (server only)

Rename package 'community-mysql' to 'mysql' and Stop providing 'mysql' symbols by package 'mariadb'

  • The package 'mariadb' will no longer be installed prefferably instead of package 'mysql' when doing "dnf install mysql" (and other subpackages)
    • Otherwise should not be noticeable to the user

Drop cross-installation functionality

  • Cross-installation functionality lost

Switch to the versioned layout of MariaDB and MySQL packages

  • Users should get the same functional results as before with the same names as before, while having differently named packages present on the system
  • Functionality lost by Modularity retirement recovered

Introduce MariaDB 10.11 and MySQL 8.1

  • New stuff that users wait for, yay \o/ !


Dependencies

Only the i686 removal should be blocked by other packages.
All other packages should keep working as they do.


Contingency Plan

Drop i686 arches

  • I'll try in F41 again

Rename package 'community-mysql' to 'mysql' and Stop providing 'mysql' symbols by package 'mariadb'

  • Revert

Drop cross-installation functionality

  • Revert

Switch to the versioned layout of MariaDB and MySQL packages

  • Revert

Introduce MariaDB 10.11 and MySQL 8.1

  • I'll try in F41 again


Documentation

Let this document and the linked resources be the documentation.

Release Notes

Will be added
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