mysqld_safe not run on RHEL7, while it runs on RHEL6 when starting mariadb

Question

I see this strange behavior when Mariadb is run on RHEL7 and RHEL6.

When I start the mariadb server on RHEL6 via service mysql start, I see mysqld_safe starts along with mysqld.

[user@divinedragon]# service mysql start
Starting mysql (via systemctl):                            [  OK  ]

[user@divinedragon]# ps aux | grep mysql
root      2398  0.0  0.0 115372  1712 ?        S    09:26   0:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --pid-file=/var/lib/mysql/divinedragon.pid
mysql     2472  2.8  3.4 798208 134576 ?       Sl   09:26   0:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --user=mysql --log-error=/var/lib/mysql/divinedragon.err --pid-file=/var/lib/mysql/divinedragon.pid
root      2503  0.0  0.0 112644   956 pts/0    S+   09:27   0:00 grep --color=auto mysql

However, when I do the same thing on RHEL7, I don't see any mysqld_safe process coming up. Here is the ouput from RHEL 7.

[user@divinedragon ~]$ sudo service mysql start
Starting mysql (via systemctl):                            [  OK  ]

[user@divinedragon ~]$ ps aux | grep mysql
mysql     2515  2.6  6.0 774616 114412 ?       Ssl  08:51   0:00 /usr/sbin/mysqld
user      2548  0.0  0.0 112644   952 pts/0    R+   08:51   0:00 grep --color=auto mysql

Can somebody shed some light in here?

Answer 1

It is stated in the mariadb and even mysql docs:

https://mariadb.com/kb/en/mariadb/systemd/

systemd services are packaged on RPM and Debian based Linux distributions. When systemd is used, mysqld_safe is not used and settings in the mysqld_safe section of configuration files will not be read or applied.

https://dev.mysql.com/doc/refman/5.7/en/server-management-using-systemd.html

On platforms for which systemd support is installed, scripts such as mysqld_safe and the System V initialization script are not installed because they are unnecessary. For example, mysqld_safe can handle server restarts, but systemd provides the same capability, and does so in a manner consistent with management of other services rather than using an application-specific program.