Searching across logs with CloudWatch Logs Insights

A single Lambda function can often generate large numbers of log streams, especially if the function scales up. It can be time-consuming to find specific information if you need to search across many log groups. To help with this, the CloudWatch Logs Insights feature provides an interface that can make it easier to search and aggregate data across thousands of individual log files.

With CloudWatch Logs Insights, you can search and analyze log data using a specialized query syntax. It performs queries over multiple log groups and provides powerful filtering using glob and regular expressions pattern matching.

Additionally, you can use Lambda Insights which adds more metrics, including memory, network and CPU usage. To use Lambda Insights, you must enable this feature on a Lambda function. From the console, in the Monitoring tools section of the Configuration page, choose Edit. Under CloudWatch Lambda Insights, choose Enhanced monitoring and then choose Save. If you are using AWS SAM to deploy applications, you must include the Insights layer in the template to activate the service:

Resources:
  MyFunction:
    Type: AWS::Serverless::Function
    Properties:
      Layers:
        - !Sub "arn:aws:lambda:${AWS::Region}:580247275435:layer:LambdaInsightsExtension:14"
      Policies:
        - CloudWatchLambdaInsightsExecutionRolePolicy

The latest available versions of the Lambda Insights extension are published in the documentation. CloudWatch Logs Insights are useful for monitoring metrics emitted by your custom code and for standard logs emitted from the Lambda service.