---
sourceDocument: Yokohama IT Operations Management
sourceDocumentLink: https://www.servicenow.com/docs/r/yokohama/it-operations-management

 Release :

    - yokohama

ft:locale :

    - en-US

ft:publication_title :

    - Yokohama IT Operations Management

ft:clusterId :

    - itom

bundleId :

    - itom

workflow :

    - Technology


---

# Purge impact status and alert history

# Purge impact status and alert history {#ariaid-title1}

* Release version: Yokohama
* 
* Updated January 30, 2025
* 
* ![](https://www.servicenow.com/docs/portal-asset/ico-clock) 1 minute to read

Automatically cleans up outdated impact statuses and alert history from the database to free up space, improve system performance, and ensure only relevant data is retained.

## Before you begin

Role required: evt_mgmt_admin

## About this task

If records are older than 90 days, by default they are purged. If records are retained for a longer period, larger volumes of data are stored, and performance may be impacted. The data cleanup is done by two jobs: Event Management - Clean Alert History Table and Event Management - Clean Impact Status Table.

## Procedure

1. Navigate to AllEvent ManagementAdministrationEvent Management Properties.
2. To shorten the retention period, use the highlighted properties.  
{#t_EMConfigurePurge__steps_w33_tkv_c5}
* **[Clean alert history and impact status tables](https://www.servicenow.com/docs/Z7McHnYoW5RcnqB8yPnGMA)**   
  Schedule jobs to mark and remove old alert records in the Alert History \[em_alert_history\] and Impact Status \[em_impact_status\] tables, to prevent the tables from becoming overloaded with data.

**Related concepts**   

* [Rotate event tables and alert table cleanup](https://www.servicenow.com/docs/EFvGJm8xCam46Sers9JrXw "The growth of data tables impedes performance. Preserve instance performance by event table rotation and alert table cleanup for status and alert history retention.")  
**Related tasks**   

* [Modify event table rotation](https://www.servicenow.com/docs/9pHN0dMNUf08JsHz7Tt4jQ "Table rotation is used by Event Management, by default, to contain the growth of event [em_event] tables within the rotation table group.")
* [Clean alert history and impact status tables](https://www.servicenow.com/docs/Z7McHnYoW5RcnqB8yPnGMA "Schedule jobs to mark and remove old alert records in the Alert History [em_alert_history] and Impact Status [em_impact_status] tables, to prevent the tables from becoming overloaded with data.")
* [Alert table clean up](https://www.servicenow.com/docs/UyRaO4w3xXqNsEX5ckV3Sg "The Scheduled Jobs feature runs a script to automatically close alerts in the Alerts [em_alert] table that meet specific conditions, helping reduce alert noise and keep the system clean and efficient.")

*[\>]: and then