# Create an alarm on Performance Insights counter metrics from an AWS database CloudWatch includes a **DB\_PERF\_INSIGHTS** metric math function which you can use to bring Performance Insights counter metrics into CloudWatch from Amazon Relational Database Service and Amazon DocumentDB (with MongoDB compatibility). **DB\_PERF\_INSIGHTS** also brings in the `DBLoad` metric at sub-minute intervals. You can set CloudWatch alarms on these metrics. For more information about Amazon RDS Performance Insights, see [ Monitoring DB load with Performance Insights on Amazon RDS](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_PerfInsights.html). For more information about Amazon DocumentDB Performance Insights, see [ Monitoring with Performance Insights](https://docs.aws.amazon.com/documentdb/latest/developerguide/performance-insights.html.html). Anomaly detection is not supported for alarms based on the **DB\_PERF\_INSIGHTS** function. **Note** High-resolution metrics with sub-minute granularity retrieved by **DB\_PERF\_INSIGHTS** are only applicable to the **DBLoad** metric, or for operating system metrics if you have enabled Enhanced Monitoring at a higher resolution. For more information about Amazon RDS enhanced monitoring, see [ Monitoring OS metrics with Enhanced Monitoring.](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Monitoring.OS.html). You can create a high-resolution alarm using the **DB\_PERF\_INSIGHTS** function. The maximum evaluation range for a high-resolution alarm is three hours. You can use the CloudWatch console to graph metrics retrieved with the **DB\_PERF\_INSIGHTS** function for any time range. **To create an alarm that's based on Performance Insights metrics** 1. Open the CloudWatch console at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/). 1. In the navigation pane, choose **Alarms**, and then choose **All alarms**. 1. Choose **Create alarm**. 1. Choose **Select Metric**. 1. Choose the **Add math** dropdown, and then select **All functions**, **DB\_PERF\_INSIGHTS** from the list. After you choose **DB\_PERF\_INSIGHTS**, a math expression box appears where you apply or edit math expressions. 1. In the math expression box, enter your **DB\_PERF\_INSIGHTS** math expression, and then choose **Apply**. For example, **DB\_PERF\_INSIGHTS(‘RDS’, ‘db-ABCDEFGHIJKLMNOPQRSTUVWXY1’, ‘os.cpuUtilization.user.avg’)** **Important** When you use the **DB\_PERF\_INSIGHTS** math expression, you must specify the Unique Database Resource ID of the database. This is different than the database identifier. To find the database resource ID in the Amazon RDS console, choose the DB instance to see its details. Then choose the **Configuration** tab. The **Resource ID** is displayed in the **Configuration** section. For information about the **DB\_PERF\_INSIGHTS** function and other functions that are available for metric math, see [Metric math syntax and functions](using-metric-math.md#metric-math-syntax). 1. Choose **Select metric**. The **Specify metric and conditions** page appears, showing a graph and other information about the math expression that you have selected. 1. For **Whenever {{expression}} is**, specify whether the expression must be greater than, less than, or equal to the threshold. Under **than...**, specify the threshold value. 1. Choose **Additional configuration**. For **Datapoints to alarm**, specify how many evaluation periods (data points) must be in the `ALARM` state to trigger the alarm. If the two values here match, you create an alarm that goes to `ALARM` state if that many consecutive periods are breaching. To create an M out of N alarm, specify a lower number for the first value than you specify for the second value. For more information, see [Alarm evaluation](alarm-evaluation.md). 1. For **Missing data treatment**, choose how to have the alarm behave when some data points are missing. For more information, see [Configuring how CloudWatch alarms treat missing data](alarms-and-missing-data.md). 1. Choose **Next**. 1. Under **Notification**, select an SNS topic to notify when the alarm is in `ALARM` state, `OK` state, or `INSUFFICIENT_DATA` state. To have the alarm send multiple notifications for the same alarm state or for different alarm states, choose **Add notification**. To have the alarm not send notifications, choose **Remove**. 1. To have the alarm perform Auto Scaling, EC2, Lambda, or Systems Manager actions, choose the appropriate button and choose the alarm state and action to perform. If you choose a Lambda function as an alarm action, you specify the function name or ARN, and you can optionally choose a specific version of the function. Alarms can perform Systems Manager actions only when they go into ALARM state. For more information about Systems Manager actions, see see [ Configuring CloudWatch to create OpsItems from alarms](https://docs.aws.amazon.com/systems-manager/latest/userguide/OpsCenter-create-OpsItems-from-CloudWatch-Alarms.html) and [ Incident creation](https://docs.aws.amazon.com/incident-manager/latest/userguide/incident-creation.html). **Note** To create an alarm that performs an SSM Incident Manager action, you must have certain permissions. For more information, see [ Identity-based policy examples for AWS Systems Manager Incident Manager](https://docs.aws.amazon.com/incident-manager/latest/userguide/security_iam_id-based-policy-examples.html). 1. When finished, choose **Next**. 1. Enter a name and description for the alarm. Then choose **Next**. The name must contain only UTF-8 characters, and can't contain ASCII control characters. The description can include markdown formatting, which is displayed only in the alarm **Details** tab in the CloudWatch console. The markdown can be useful to add links to runbooks or other internal resources. 1. Under **Preview and create**, confirm that the information and conditions are what you want, then choose **Create alarm**.