pt-online-schema-change utf8mb4 错误解决方法

Character set ‘utf8mb4’ is not a compiled character set and is not specified in the ‘/usr/share/mysql/charsets/Index.xml’ file
Character set ‘utf8mb4’ is not a compiled character set and is not specified in the ‘/usr/share/mysql/charsets/Index.xml’ file
Cannot connect to MySQL: DBI connect(‘med_data;host=127.0.0.1;mysql_read_default_group=client’,’root’,…) failed: Can’t initialize character set utf8mb4 (path: /usr/share/mysql/charsets/) at /usr/bin/pt-online-schema-change line 2281