Review Database Deployment Metrics
On this page
Atlas collects and displays metrics for your servers, databases, and MongoDB processes.
Monitor database deployment metrics to identify performance issues and determine whether your current database deployment meets your requirements. For more information on the metrics available to monitor your database deployments, see Review Available Metrics.
The number of servers that Atlas displays on the
Metrics page at any given time depends on the browser
screen size. Use the Toggle Members section to control
which servers Atlas displays. Hover over the S and P
icons to find out which servers they represent.
View Metrics
You can view metrics in the following ways:
- Project Overview
- The Overview tab displays all the database deployments in an Atlas project and features core metrics per database deployment.
- Atlas Serverless Instances
- View the metrics for a specific serverless instance in an Atlas project.
- Atlas Replica Sets
- View the metrics for a specific replica set in an Atlas project.
- Atlas Sharded Clusters
- View the metrics for a specific sharded cluster in an Atlas project.
- MongoDB Processes
- View the metrics for a specific MongoDB process in an Atlas cluster.
- Real-Time Performance
- View real-time performance metrics for a specific Atlas database deployment in a project.
- Atlas Search
- View Atlas Search metrics for Atlas clusters with at least one active Atlas Search index.
Important Metrics
You can monitor the following metrics to quickly gauge the health of your database deployment.
Chart | Description |
|---|---|
Connections | Number that indicates the total active connections to the database deployment. Monitor connections to determine whether the current connection limits are sufficient. If necessary, upgrade the cluster tier. To learn more, see Fix Connection Issues and Fix Lost Primary. |
Disk IOPS | Number that indicates the input operations per second. Monitor whether disk IOPS approaches the maximum provisioned IOPS. Determine whether the cluster can handle future workloads. To learn more, see Fix IOPS Issues and Fix Lost Primary. |
Disk Usage | Number that indicates the total bytes of used disk space for the cluster. Monitor the combined size of your data and MongoDB operational data (buffer, journal, and log files) on the cluster. To learn more, see Fix Storage Issues. |
Query Targeting | Number that indicates the efficiency of read operations run on MongoDB. Monitor query targeting metrics to identify inefficent queries. To learn more, see Fix Query Issues. |
Normalized System CPU | Number that indicates CPU usage of all processes on the node, scaled to a range of 0-100% by dividing by the number of CPU cores. Monitor CPU usage to determine whether data is retrieved from disk instead of memory. To learn more, see Fix IOPS Issues, Fix Lost Primary, and Fix CPU Usage Issues. |
Oplog GB/Hour | Number that indicates the average rate in gigabytes of oplog data that the primary generates per hour. Monitor oplog data to determine whether you have to increase the oplog size. To learn more, see Fix Oplog Issues. |
Util % | Percentage of time that requests are issued to and serviced by disk. This metric includes requests from any process, not just MongoDB processes. Monitor whether utilization is high. Determine whether to increase the provisioned IOPS or upgrade the cluster. To learn more, see Fix IOPS Issues. |
Monitoring Data Storage Granularity
Atlas stores metrics data at increasing granularity levels. For each increasing granularity level, Atlas computes the metrics data based on the averages from the previous granularity level. The length of retention depends on the granularity. Atlas computes the metrics data based on the averages from the previous granularity level.
Atlas gathers metrics data at a 1-minute granularity unless you qualify for premium monitoring.
After 48 hours' worth of data is collected, each group of 60 minutes is compacted into a single unit of an hour. After 63 days, each group of 24 hours is compacted into a single unit of a day.
Premium Monitoring Granularity
If you have at least one cluster that's M40 or larger, Atlas
automatically enables premium monitoring for all clusters in the project. With
premium monitoring enabled, Atlas gathers metrics data at a 10-second
granularity. Premium monitoring remains enabled for all clusters in the project until you
downgrade or terminate your last M40 cluster.
Premium monitoring will become available in stages. If you have an M40
cluster or larger but don't see the premium monitoring granularity yet, you
should see it soon.
Metrics Data Retention
Atlas retains metrics data for a period of time that depends on the granularity of the data:
Data Period | Duration of Retention |
|---|---|
10 seconds | 8 hours |
1 minute | 48 hours |
5 minutes | 48 hours |
1 hour | 63 days |
1 day | Forever |
Premium monitoring only.
Atlas retains all database-specific statistics. MongoDB log data is retained at a maximum rate of 2000 lines per 2 minutes.
Free Cluster and Shared Cluster Monitoring Considerations
M0free clusters andM2/M5shared clusters support a subset of the metrics and charts available. For complete documentation on the limitations ofM0/M2/M5clusters, see Atlas M0 (Free Cluster), M2, and M5 Limitations.- Atlas pauses monitoring for
M0free clusters which have had no connection activity for 7 days. Monitoring resumes once a successful connection occurs through the Atlas Administration API, Driver,mongosh, or Data Explorer.
Serverless Instance Monitoring Considerations
- Serverless instances support a subset of the metrics and charts available. For complete documentation on the limitations of serverless instances, see Serverless Instance Limitations.