liushiyi@liushiyiPC ~ $ which mysqld
/usr/sbin/mysqld
liushiyi@liushiyiPC ~ $ mysqld --verbose --help|grep -A 1 'Default options'
mysqld: One can only use the --user switch if running as root
180825 16:41:57 [Note] Plugin 'FEEDBACK' is disabled.
180825 16:41:57 [Warning] Could not open mysql.plugin table. Some options may be missing from the help text
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf ~/.my.cnf