Quickly and efficiently migrating hundreds of servers from MySQL to MariaDB

Via SpamExperts:

SpamExperts has their own anti-spam filtering cloud which is provided as a software-as-a-service (SaaS) model. In addition they have an e-mail security product which they install, update and monitor on-site. Most of SpamExperts’ anti-spam technology has been developed in-house and makes extensive use of the MySQL database. All clients contribute in real-time to their filtering effectiveness, so they have many different data flows that are handled by MySQL. Replication is used to synchronize the data between the systems in a cluster and to push data feeds in real-time. The SaaS cloud is replicated across four countries for redundancy, whereas client installations spread the data retrieval around the globe.

After extensive testing, SpamExperts managed the efficient migration of approximately three hundred servers from MySQL to MariaDB within three hours. “In the past we have run into various MySQL bugs. Despite the fact that we reported them, the bugs were still not solved after a year,” says Dreas van Donselaar Chief Technology Officer for SpamExperts B.V. “There were bugs in the upgrade procedure from MySQL 5.0 to MySQL 5.1, thus preventing us from using the entire new 5.1 feature-set”.

“MariaDB had the same bugs that we ran into with MySQL. However the big difference was that when we reported these bugs, they were quickly resolved within 48 hours!” exclaimed Dreas. The quick turnaround time bolstered confidence in the quality of the MariaDB product and its support and development teams.

During the testing phases, SpamExperts discovered a few bugs during the conversion that affected about 5% of their systems: long table names were not correctly converted, the thread_stack was too low on certain systems for MariaDB 5.1 which resulted in some crashes, newly created tables during the conversion resulted in table name conflicts and replication breakage due to table name changes. These bugs were all present in MySQL and have since been resolved in the MariaDB codebase. This process was resolved generally using Internet Relay Chat (IRC) on the #maria channel on irc.freenode.net.

Asked how SpamExperts is enjoying the use of MariaDB after a couple months of usage, Dreas responds: “Its running great! We have not encountered any major new issues. Its very nice to work with a team that is so passionate about its software and we believe it should allow MariaDB to quickly become the next relational database standard.”