mariadb лимит на файлы поднять centos 7 systemd

mkdir /etc/systemd/system/mariadb.service.d/

printf '[Service]\nLimitNOFILE = infinity\nLimitMEMLOCK = infinity\n' >> /etc/systemd/system/mariadb.service.d/limits.conf

systemctl daemon-reload
systemctl restart mariadb