Metrics analyzed by AWS Compute Optimizer - AWS Compute Optimizer

Metrics analyzed by AWS Compute Optimizer

After you opt in, AWS Compute Optimizer begins analyzing the specifications (vCPUs, memory, storage, and so on) and the CloudWatch metrics of your running resources from a period of the last 14 days. Compute Optimizer requires at least 30 consecutive hours of metrics data from your resource to generate recommendations. After the analysis is completed, which could take up to 12 hours, Compute Optimizer presents its findings on the dashboard page. For more information, see Viewing the AWS Compute Optimizer dashboard.

EC2 instance metrics

Compute Optimizer analyzes the following CloudWatch metrics of your EC2 instances, including instances that are part of Auto Scaling groups.

Metric Description
CPUutilization

The percentage of allocated EC2 compute units that are in use on the instance. This metric identifies the processing power required to run an application on an instance.

Memory utilization

The amount of memory that has been used in some way during the sample period. This metric identifies the memory required to run an application on an instance.

Memory utilization is analyzed only for resources that have the unified CloudWatch agent installed on them. For more information, see Enabling memory utilization with the CloudWatch Agent.

NetworkIn

The number of bytes received on all network interfaces by the instance. This metric identifies the volume of incoming network traffic to an instance.

NetworkOut

The number of bytes sent out on all network interfaces by the instance. This metric identifies the volume of outgoing network traffic from an instance.

NetworkPacketsIn

The number of packets received by the instance.

NetworkPacketsOut

The number of packets sent out by the instance.

DiskReadOps

The read operations per second of the instance store volume of the instance.

DiskWriteOps

The write operations per second of the instance store volume of the instance.

DiskReadBytes

The read bytes per second of the instance store volume of the instance.

DiskWriteBytes

The write bytes per second of the instance store volume of the instance.

VolumeReadBytes

The read bytes per second (displayed as KiB/seconds in the console) of EBS volumes attached to the instance.

VolumeWriteBytes

The write bytes per second (displayed as KiB/seconds in the console) of EBS volumes attached to the instance.

VolumeReadOps

The read operations per second of EBS volumes attached to the instance.

VolumeWriteOps

The write operations per second of EBS volumes attached to the instance.

For more information about instance metrics, see List the available CloudWatch metrics for your instances in the Amazon Elastic Compute Cloud User Guide. For more information about EBS volume metrics, see Amazon CloudWatch metrics for Amazon EBS in the Amazon Elastic Compute Cloud User Guide.

Enabling memory utilization with the CloudWatch Agent

Install the CloudWatch agent on your instances to have Compute Optimizer analyze the memory utilization of your instances. Enabling Compute Optimizer to analyze memory utilization data for your instances provides an additional measurement of data that further improves the recommendations provided by the service. For more information about installing the CloudWatch agent, see Collecting Metrics and Logs from Amazon EC2 Instances and On-Premises Servers with the CloudWatch Agent in the Amazon CloudWatch User Guide.

On Linux instances, Compute Optimizer analyses the mem_used_percent metric in the CWAgent namespace, or the legacy MemoryUtilization metric in the System/Linux namespace. On Windows instances, Compute Optimizer analyses the Memory % Committed Bytes In Use metric in the CWAgent namespace. Additionally, the namespace must contain the InstanceId dimension. Compute Optimizer will not be able to collect memory utilization data for your instance if the InstanceId dimension is missing, or if you overwrite it with your own custom dimension name. Namespaces and dimensions are defined in the CloudWatch Agent configuration file. For more information, see Create the CloudWatch Agent Configuration File in the Amazon CloudWatch User Guide.

EBS volume metrics

Compute Optimizer analyzes the following CloudWatch metrics of your EBS volumes.

Metric Description
VolumeReadBytes

The read bytes per second of the EBS volume.

VolumeWriteBytes

The write bytes per second of the EBS volume.

VolumeReadOps

The read operations per second of the EBS volume.

VolumeWriteOps

The write operations per second of the EBS volume.

For more information about these metrics, see Amazon CloudWatch metrics for Amazon EBS in the Amazon Elastic Compute Cloud User Guide.

Lambda function metrics

Compute Optimizer analyzes the following CloudWatch metrics of your Lambda functions.

Metric Description
Invocations

The number of times your function code is executed, including successful executions and executions that result in a function error.

Duration

The amount of time that your function code spends processing an event.

Errors

The number of invocations that result in a function error. Function errors include exceptions thrown by your code and exceptions thrown by the Lambda runtime. The runtime returns errors for issues such as timeouts and configuration errors.

Throttles

The number of invocation requests that are throttled.

For more information about these metrics, see Working with AWS Lambda function metrics in the AWS Lambda Developer Guide.

In addition to these metrics, Compute Optimizer analyzes the memory utilization of your function during the look-back period. For more information about memory utilization for Lambda functions, see Understanding AWS Lambda behavior using Amazon CloudWatch Logs Insights in the AWS Management & Governance Blog and Using Lambda Insights in CloudWatch in the AWS Lambda Developer Guide.