@Félix Voituret Can you please fine tune the Ambari by following https://community.hortonworks.com/articles/80635/optimize-ambari-performance-for-large-clusters.html Also you did not mentioned which ambari version ru using. If you think there is larger historical data then you can attempt to purge by following https://docs.hortonworks.com/HDPDocuments/Ambari-2.6.2.0/bk_ambari-administration/content/purging-ambari-server-history.html Let me know if any questions. ... View more