If there a change in any connections with any CI that belong to any type of service we are triggering rebuild to the serviceDescriptionWhenever there is a change in the connection of the CI belonging any type of service, we are triggering rebuild of the service.Which in turn cause the impact tree rebuilding and causing huge data to be captured in the em_impact_graph and em_impact_status tables.Steps to Reproduce Login to affected instanceCheck if the sa_notification table is filled with infra_cis_changes notification.After this check the em_impact_status & the em_impact_graph table is filled with large data.WorkaroundThis problem is currently under review. You can contact ServiceNow Technical Support or subscribe to this Known Error article by clicking the Subscribe button at the top right of this form to be notified when more information will become available.Related Problem: PRB1440124