Unable to start MySQL/MariaDB service: InnoDB: Waiting for the background threads to start

Symptoms

Unable to start MySQL/MariaDB service with the following error shown in a loop:

InnoDB: Waiting for the background threads to start. 

Cause

MySQL/MariaDB misconfiguration.

Resolution

1. Connect to the server via SSH;

2. Edit configuration file /etc/my.cnf (for CentOS) or /etc/mysql/my.cnf (for Ubuntu/Debian) using vi editor and add the following option in [mysqld] section:

   innodb_purge_threads=0

   Note: if the MySQL/MariaDB version is >=5.6.5, set this value to 1. MySQL/MariaDB version may be found in Tools & Settings > Server Components.

3. Start MySQL/MariaDB service:

   For RHEL/CentOS:

   # systemctl start mariadb

   For Ubuntu/Debian:

   # systemctl start mysql

Additional Information

https://dev.mysql.com/doc/refman/5.6/en/innodb-parameters.html#sysvar_innodb_purge_threads