Mariadb repaire
systemctl stop mariadb myisamchk -r -q /var/lib/mysql/*/*.MYI systemctl start mariadb
systemctl stop mariadb myisamchk -r -q /var/lib/mysql/*/*.MYI systemctl start mariadb
https://www.liquidweb.com/kb/how-to-upgrade-mariadb-5-5-to-mariadb-10-0-on-centos-7/ mysql_upgrade –protocol=tcp -P 3306 -u root -p https://mariadb.com/kb/en/library/performance-schema-overview/
https://dev.mysql.com/doc/refman/8.0/en/memory-use.html