Replace MySQL with MariaDB
MariaDB, a community developed fork of MySQL, will be the default implementation of MySQL in Fedora 19.
- Targeted release: Fedora 19
- Last updated: 2013-01-16
- Percentage of completion: 60%
MariaDB is a fork of the MySQL database project that provides a drop-in replacement for MySQL. It preserves API/ABI compatibility with MySQL and adds some new features.
The original company behind MySQL, MySQL AB, were bought out by Sun which was then bought by Oracle. Recent changes made by Oracle indicate they are moving the MySQL project to be more closed. They are no longer publishing any useful information about security issues (CVEs), and they are not providing complete regression tests any more, and a very large fraction of the mysql bug database is now not public.
MariaDB, which was founded by some of the original MySQL developers, has a more open-source attitude and an active community. We have found them to be much easier to work with, especially in regards to security matters.
We would like to replace MySQL with MariaDB in early development cycle for Fedora 19. MySQL will continue to be available for at least one release, but MariaDB will become the default. Also, we do not intend to support concurrent installation of both packages on the same machine; pick one or the other.
Benefit to Fedora
Fedora will have a truly open-source MySQL implementation and won't depend on what Oracle decides to do with MySQL in the future. Compared to MySQL, MariaDB is faster in some cases, it includes some new engines and features, while the existing engines and features are enhanced and still compatible.
MariaDB is binary compatible with MySQL of the same major version, so we don't need to change anything in packages depending on libmysqlclient.so. (We will be replacing mysql 5.5 with mariadb 5.5, so there are no cross-major-version changes to worry about.)
However, the embedded-mysql library libmysqld.so has changed soname, because we had to create this library manually before, while MariaDB supports it out-of-the-box now. As a consequence, packages depending on the mysql-embedded package will have to be rebuilt (currently only amarok).
Admins shouldn't notice any change.
How To Test
We need to test switching from MySQL to MariaDB on some large production databases. We will have some larger database and MySQL will be running. At this point updating to MariaDB will be done and should process cleanly. After RPM update, database will be checked from database POV and users POV. Dump of the database should be the same and users shouldn't notice any change. We will need to test also connectors and applications using mysql client library.
- There are no end-user visible changes, except the database being faster and more reliable.
- Packages structure and their contents are similar to MySQL and the changes are usually just some new files.
- Dependencies are unchanged from MySQL.
Switching back to MySQL if necessary should be easy.
We intend to mark the mariadb packages as providing/obsoleting mysql. In event that mariadb is not accepted as default, we'd just remove these markings. It will also be necessary to adjust (or revert) anaconda's idea of the packages to install when asked for a mysql database.
Main differences between MariaDB and MySQL are listed in https://kb.askmonty.org/en/mariadb-versus-mysql-features/
Compatibility between MariaDB and MySQL is discussed in https://kb.askmonty.org/en/mariadb-versus-mysql-compatibility/
Package Review is available in https://bugzilla.redhat.com/show_bug.cgi?id=875150
Some related discussions took place on fedora-devel-list: http://lists.fedoraproject.org/pipermail/devel/2012-December/175269.html
MariaDB, an improved and more open fork of the MySQL database project, has replaced original MySQL as the default mysql-compatible database. This change should be transparent to almost all MySQL users. However, if you encounter difficulties, you can replace MariaDB with the original mysql packages. (TODO: specify package names to install/remove to do this.)