# Viewing OS metrics in the RDS console You can view OS metrics reported by Enhanced Monitoring in the RDS console by choosing **Enhanced monitoring** for **Monitoring**. The following example shows the Enhanced Monitoring page. For descriptions of the Enhanced Monitoring metrics, see [OS metrics in Enhanced Monitoring](USER_Monitoring-Available-OS-Metrics.md). ![\[Dashboard view\]](http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/images/metrics1.png) Some DB instances use more than one disk for the DB instance's data storage volume. On those DB instances, the **Physical Devices** graphs show metrics for each one of the disks. For example, the following graph shows metrics for four disks. ![\[Graph with multiple disks\]](http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/images/enhanced-monitoring-multiple-disks.png) **Note** Currently, **Physical Devices** graphs are not available for Microsoft SQL Server DB instances. When you are viewing aggregated **File system** graphs, the **rdsdbdata\$1** device relates to the `rdsfilesys/rdsdbdata*` file system, where all database files and logs are stored. The **rootfilesys** device relates to the `/` file system (also known as root), where files related to the operating system are stored. When using additional storage volumes, view the `rdsdbdata2`, `rdsdbdata3`, and `rdsdbdata4` volume metrics for volume specific information. When you are viewing aggregated **Disk I/O** graphs, the **rdsdbdata** device relates to the primary `/rdsdbdata` storage volume. When using additional storage volumes, view the `rdsdbdata2`, `rdsdbdata3`, and `rdsdbdata4` volume metrics for volume specific information. The filesystem device relates to the /file system (also known as root), where files related to the operating system are stored. The **rdsdev** device name is deprecated. The **rdsdev** device only relates to the primary `/rdsdbdata` storage volume and does not include metrics from additional storage volumes. ![\[Graph showing file system usage\]](http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/images/enhanced-monitoring-filesystem.png) If the DB instance is a Multi-AZ deployment, you can view the OS metrics for the primary DB instance and its Multi-AZ standby replica. In the **Enhanced monitoring** view, choose **primary** to view the OS metrics for the primary DB instance, or choose **secondary** to view the OS metrics for the standby replica. ![\[Primary and secondary choice for Enhanced Monitoring\]](http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/images/enhanced-monitoring-primary-secondary.png) For more information about Multi-AZ deployments, see [Configuring and managing a Multi-AZ deployment for Amazon RDS](Concepts.MultiAZ.md). **Note** Currently, viewing OS metrics for a Multi-AZ standby replica is not supported for MariaDB DB instances. If you want to see details for the processes running on your DB instance, choose **OS process list** for **Monitoring**. The **Process List** view is shown following. ![\[Process list view\]](http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/images/metrics2.png) The Enhanced Monitoring metrics shown in the **Process list** view are organized as follows: + **RDS child processes** – Shows a summary of the RDS processes that support the DB instance, for example `mysqld` for MySQL DB instances. Process threads appear nested beneath the parent process. Process threads show CPU utilization only as other metrics are the same for all threads for the process. The console displays a maximum of 100 processes and threads. The results are a combination of the top CPU consuming and memory consuming processes and threads. If there are more than 50 processes and more than 50 threads, the console displays the top 50 consumers in each category. This display helps you identify which processes are having the greatest impact on performance. + **RDS processes** – Shows a summary of the resources used by the RDS management agent, diagnostics monitoring processes, and other AWS processes that are required to support RDS DB instances. + **OS processes** – Shows a summary of the kernel and system processes, which generally have minimal impact on performance. The items listed for each process are: + **VIRT** – Displays the virtual size of the process. + **RES** – Displays the actual physical memory being used by the process. + **CPU%** – Displays the percentage of the total CPU bandwidth being used by the process. + **MEM%** – Displays the percentage of the total memory being used by the process. The monitoring data that is shown in the RDS console is retrieved from Amazon CloudWatch Logs. You can also retrieve the metrics for a DB instance as a log stream from CloudWatch Logs. For more information, see [Viewing OS metrics using CloudWatch Logs](USER_Monitoring.OS.CloudWatchLogs.md). Enhanced Monitoring metrics are not returned during the following: + A failover of the DB instance. + Changing the instance class of the DB instance (scale compute). Enhanced Monitoring metrics are returned during a reboot of a DB instance because only the database engine is rebooted. Metrics for the operating system are still reported.