I looked at the mysql-5.6 package in the xenial distribution.
It provides 3 init scripts: one for upstart, one for SysV init, and one
presumably for systemd. Each provides a different value for the server
to shutdown: 10 seconds, 300 seconds or 600 seconds, depending on which
service you use.
I
Public bug reported:
In `/etc/init/mysql.conf`, the configuration is set to wait 5 minutes
after a SIGTERM is issued before a SIGKILL is issued. The value was
intentionally set that high because sometimes the default of 5 seconds
wasn't long enough [1].
1. https://bugs.launchpad.net/ubuntu/+sour
