Amazon CloudWatch metrics for Amazon RDS - Amazon Relational Database Service

Amazon CloudWatch metrics for Amazon RDS

Amazon CloudWatch metrics provide insights into the performance and health of Amazon RDS instances and clusters, allowing you to monitor system behavior and make data-driven decisions. These metrics help track resource utilization, database activity, and operational efficiency, offering visibility into how your instances are performing.

This reference outlines the specific metrics available for Amazon RDS and explains how to interpret and use them to optimize database performance, troubleshoot issues, and ensure high availability.

Amazon RDS publishes metrics to Amazon CloudWatch in the AWS/RDS and AWS/Usage namespaces.

Amazon CloudWatch instance-level metrics for Amazon RDS

The AWS/RDS namespace in Amazon CloudWatch includes the following instance-level metrics.

Note

The Amazon RDS console might display metrics in units that are different from the units sent to Amazon CloudWatch. For example, the Amazon RDS console might display a metric in megabytes (MB), while the metric is sent to Amazon CloudWatch in bytes.

Metric Description Applies to Units

BinLogDiskUsage

The amount of disk space occupied by binary logs. If automatic backups are enabled for MySQL and MariaDB instances, including read replicas, binary logs are created.

MariaDB

MySQL

Bytes

BurstBalance

The percent of General Purpose SSD (gp2) burst-bucket I/O credits available.

All

Percent

CheckpointLag

The amount of time since the most recent checkpoint.

Seconds

ConnectionAttempts

The number of attempts to connect to an instance, whether successful or not.

MySQL

Count

CPUUtilization

The percentage of CPU utilization.

All

Percentage

CPUCreditUsage

The number of CPU credits spent by the instance for CPU utilization. One CPU credit equals one vCPU running at 100 percent utilization for one minute or an equivalent combination of vCPUs, utilization, and time. For example, you might have one vCPU running at 50 percent utilization for two minutes or two vCPUs running at 25 percent utilization for two minutes.

This metric applies only to db.t2, db.t3, and db.t4g instances.
Note

We recommend using the T DB instance classes only for development and test servers, or other non-production servers. For more details on the T instance classes, see DB instance class types

CPU credit metrics are available at a five-minute frequency only. If you specify a period greater than five minutes, use the Sum statistic instead of the Average statistic.

Credits (vCPU-minutes)

CPUCreditBalance

The number of earned CPU credits that an instance has accrued since it was launched or started. For T2 Standard, the CPUCreditBalance also includes the number of launch credits that have been accrued.

Credits are accrued in the credit balance after they are earned, and removed from the credit balance when they are spent. The credit balance has a maximum limit, determined by the instance size. After the limit is reached, any new credits that are earned are discarded. For T2 Standard, launch credits don't count towards the limit.

The credits in the CPUCreditBalance are available for the instance to spend to burst beyond its baseline CPU utilization.

When an instance is running, credits in the CPUCreditBalance don't expire. When the instance stops, the CPUCreditBalance does not persist, and all accrued credits are lost.

CPU credit metrics are available at a five-minute frequency only.

This metric applies only to db.t2, db.t3, and db.t4g instances.
Note

We recommend using the T DB instance classes only for development and test servers, or other non-production servers. For more details on the T instance classes, see DB instance class types

Launch credits work the same way in Amazon RDS as they do in Amazon EC2. For more information, see Launch credits in the Amazon Elastic Compute Cloud User Guide for Linux Instances.

Credits (vCPU-minutes)

CPUSurplusCreditBalance

The number of surplus credits that have been spent by an unlimited instance when its CPUCreditBalance value is zero.

The CPUSurplusCreditBalance value is paid down by earned CPU credits. If the number of surplus credits exceeds the maximum number of credits that the instance can earn in a 24-hour period, the spent surplus credits above the maximum incur an additional charge.

CPU credit metrics are available at a 5-minute frequency only.

All

Credits (vCPU-minutes)

CPUSurplusCreditsCharged

The number of spent surplus credits that are not paid down by earned CPU credits, and which thus incur an additional charge.

Spent surplus credits are charged when any of the following occurs:

  • The spent surplus credits exceed the maximum number of credits that the instance can earn in a 24-hour period. Spent surplus credits above the maximum are charged at the end of the hour.

  • The instance is stopped or terminated.

  • The instance is switched from unlimited to standard.

CPU credit metrics are available at a 5-minute frequency only.

All

Credits (vCPU-minutes)

DatabaseConnections

The number of client network connections to the database instance.

The number of database sessions can be higher than the metric value because the metric value doesn't include the following:

  • Sessions that no longer have a network connection but which the database hasn't cleaned up

  • Sessions created by the database engine for its own purposes

  • Sessions created by the database engine's parallel execution capabilities

  • Sessions created by the database engine job scheduler

  • Amazon RDS connections

All

Count

DiskQueueDepth

The number of outstanding I/Os (read/write requests) waiting to access the disk.

All

Count

DiskQueueDepthLogVolume

The number of outstanding I/Os (read/write requests) waiting to access the log volume disk.

All

Count

EBSByteBalance%

The percentage of throughput credits remaining in the burst bucket of your RDS database. This metric is available for basic monitoring only.

The metric value is based on the throughput of all volumes, including the root volume, rather than on only those volumes containing database files.

To find the instance sizes that support this metric, see the instance sizes with an asterisk (*) in the EBS optimized by default table in Amazon EC2 User Guide. The Sum statistic is not applicable to this metric.

All

Percentage

EBSIOBalance%

The percentage of I/O credits remaining in the burst bucket of your RDS database. This metric is available for basic monitoring only.

The metric value is based on the IOPS of all volumes, including the root volume, rather than on only those volumes containing database files.

To find the instance sizes that support this metric, see Amazon EBS–optimized instance types in Amazon EC2 User Guide. The Sum statistic isn't applicable to this metric.

This metric is different from BurstBalance. To learn how to use this metric, see Improving application performance and reducing costs with Amazon EBS-Optimized Instance burst capability.

All

Percentage

FailedSQLServerAgentJobsCount

The number of failed Microsoft SQL Server Agent jobs during the last minute.

Microsoft SQL Server

Count per minute

FreeableMemory

The amount of available random access memory.

For MariaDB, MySQL, Oracle, and PostgreSQL DB instances, this metric reports the value of the MemAvailable field of /proc/meminfo.

All

Bytes

FreeLocalStorage

The amount of available local storage space.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Bytes

FreeLocalStoragePercent

The percentage of available local storage space.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Percentage

FreeStorageSpace

The amount of available storage space.

All

Bytes

FreeStorageSpaceLogVolume

The amount of available storage space on the log volume.

All

Bytes

MaximumUsedTransactionIDs

The maximum transaction IDs that have been used.

PostgreSQL

Count

NetworkReceiveThroughput

The incoming (receive) network traffic on the DB instance, including both customer database traffic and Amazon RDS traffic used for monitoring and replication.

All

Bytes per second

NetworkTransmitThroughput

The outgoing (transmit) network traffic on the DB instance, including both customer database traffic and Amazon RDS traffic used for monitoring and replication.

All

Bytes per second

OldestReplicationSlotLag

The lagging size of the replica lagging the most in terms of write-ahead log (WAL) data received.

PostgreSQL

Bytes

ReadIOPS

The average number of disk read I/O operations per second.

All

Count per second

ReadIOPSLocalStorage

The average number of disk read I/O operations to local storage per second.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Count per second

ReadIOPSLogVolume

The average number of disk read I/O operations per second for the log volume.

All

Count per second

ReadLatency

The average amount of time taken per disk I/O operation.

All

Seconds

ReadLatencyLocalStorage

The average amount of time taken per disk I/O operation for local storage.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Seconds

ReadLatencyLogVolume

The average amount of time taken per disk I/O operation for the log volume.

All

Seconds

ReadThroughput

The average number of bytes read from disk per second.

All

Bytes per second

ReadThroughputLocalStorage

The average number of bytes read from disk per second for local storage.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Bytes per second

ReadThroughputLogVolume

The average number of bytes read from disk per second for the log volume.

All

Bytes per second

ReplicaLag

For read replica configurations, the amount of time a read replica DB instance lags behind the source DB instance. Applies to MariaDB, Microsoft SQL Server, MySQL, Oracle, and PostgreSQL read replicas.

For Multi-AZ DB clusters, the difference in time between the latest transaction on the writer DB instance and the latest applied transaction on a reader DB instance.

Seconds

ReplicationChannelLag

For multi-source replica configurations, the amount of time a particular channel on the multi-source replica lags behind the source DB instance. For more information, see Monitoring multi-source replication channels.

MySQL

Seconds

ReplicationSlotDiskUsage

The disk space used by replication slot files.

PostgreSQL

Bytes

SwapUsage

The amount of swap space used on the DB instance.

MariaDB

MySQL

Oracle

PostgreSQL

Bytes

TransactionLogsDiskUsage

The disk space used by transaction logs.

PostgreSQL

Bytes

TransactionLogsGeneration

The size of transaction logs generated per second.

PostgreSQL

Bytes per second

WriteIOPS

The average number of disk write I/O operations per second.

All

Count per second

WriteIOPSLocalStorage

The average number of disk write I/O operations per second on local storage.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Count per second

WriteIOPSLogVolume

The average number of disk write I/O operations per second for the log volume.

All

Count per second

WriteLatency

The average amount of time taken per disk I/O operation.

All

Seconds

WriteLatencyLocalStorage

The average amount of time taken per disk I/O operation on local storage.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Seconds

WriteLatencyLogVolume

The average amount of time taken per disk I/O operation for the log volume.

All

Seconds

WriteThroughput

The average number of bytes written to disk per second.

All

Bytes per second

WriteThroughputLogVolume

The average number of bytes written to disk per second for the log volume.

All

Bytes per second

WriteThroughputLocalStorage

The average number of bytes written to disk per second for local storage.

This metric only applies to DB instance classes with NVMe SSD instance store volumes. For information about Amazon EC2 instances with NVMe SSD instance store volumes, see Instance store volumes. The equivalent RDS DB instance classes have the same instance store volumes. For example, the db.m6gd and db.r6gd DB instance classes have NVMe SSD instance store volumes.

Bytes per second

Amazon CloudWatch usage metrics for Amazon RDS

The AWS/Usage namespace in Amazon CloudWatch includes account-level usage metrics for your Amazon RDS service quotas. CloudWatch collects usage metrics automatically for all AWS Regions.

For more information, see CloudWatch usage metrics in the Amazon CloudWatch User Guide. For more information about quotas, see Quotas and constraints for Amazon RDS and Requesting a quota increase in the Service Quotas User Guide.

Metric Description Units*
AllocatedStorage

The total storage for all DB instances. The sum excludes temporary migration instances.

Gigabytes

DBClusterParameterGroups

The number of DB cluster parameter groups in your AWS account. The count excludes default parameter groups.

Count

DBClusters

The number of Amazon Aurora DB clusters in your AWS account.

Count

DBInstances

The number of DB instances in your AWS account.

Count

DBParameterGroups

The number of DB parameter groups in your AWS account. The count excludes the default DB parameter groups.

Count

DBSecurityGroups

The number of security groups in your AWS account. The count excludes the default security group and the default VPC security group.

Count

DBSubnetGroups

The number of DB subnet groups in your AWS account. The count excludes the default subnet group.

Count

ManualClusterSnapshots

The number of manually created DB cluster snapshots in your AWS account. The count excludes invalid snapshots.

Count

ManualSnapshots

The number of manually created DB snapshots in your AWS account. The count excludes invalid snapshots.

Count

OptionGroups

The number of option groups in your AWS account. The count excludes the default option groups.

Count

ReservedDBInstances

The number of reserved DB instances in your AWS account. The count excludes retired or declined instances.

Count

Note

Amazon RDS doesn't publish units for usage metrics to CloudWatch. The units only appear in the documentation.