A few minutes ago I performed an update of a system that had MariaDB installed and the installation got stuck at "Cleanup : MariaDB-server-5.5.42-1.el6.x86_64" for about 20 minutes.
Apparently the rpm restarted the server which is a really really bad idea.
First this created an unexpected downtime of the service as the actual restart of the system was scheduled for a later time.
Second had the system crashed during that long time window not only the MariaDB database would be affected but the package database would be corrupt as well.
Please remove this restart from the rpm as it interferes with the controlled maintenance of the system and makes us admins really sad pandas .