Currently we have one database cluster with 15 different schemas – these schemas could be either schemas which contain “real” data, or just schemas with metadata.

I guess the next evolutionary step of our database stack would be to split up the database cluster vertically along these schemas. All the data schemas should be moved to standalone mysql instances, and put the metadata schemas next to them. This also could be a good project for prepare to move a certain part of database for example to a cloud provider while other parts are still kept on bare metal.

I started wondering what could be the best way to split MySQL instances in a single hardware. I have the following ideas:

• Hack init scripts to start different instances on different ports (and log directories, data directories, config files too)
• Use mysqld_multi
• Use MySQL Sandbox
• Use docker

The first …

Normally I like to use the OS’s package manager to manage the software on my system. This ensures that things are done consistently. When managing MySQL I’d also like to manage all my instances the same way. That makes life easier for me but also for my fellow DBAs and sysadmin colleagues.

I use CentOS and the rpm packages it provides and these work quite well. However, the MySQL rpms do not allow me to manage single and multiple instances alike and while mysqld runs as the mysql user the instance management needs to be done as root (stopping, starting instances, or default access). If you want to run multiple instances you can also use mysqld_multi, but that’s not the default setup.

So this is not ideal. While this may not be much of an issue if you manage a single server, if you manage tens or …