Para quem quer corrigir esse problema, aqui está a solução.
Referência : link
By default, Parallels Plesk Panel does not use Apache graceful restart for applying new settings. As result Apache will be restarted every time you change hosting settings through the Plesk GUI. This can lead to unwanted interruptions of sites operation.
Solução
INSERT INTO 'misc' VALUES ('restart_apache_gracefully', 'true') ON DUPLICATE KEY UPDATE 'val' = 'true';