CloudWatch Lambda Insights | Overview.

Amazon CloudWatch Lambda Insights - Overview.

Scope:

• Intro,
• Key Features and Benefits,
• Enabling Lambda Insights,
• The Concept: Lambda Insights,
• How It Works (Architecture Flow),
• Metrics Collected (Beyond Standard Lambda),
• Sample Logs Structured Report (Lambda Insights adds),
• Enabling Lambda Insights,
• Integrations,
• Advanced Use Cases,
• IAM Permissions Needed (The Lambda’s execution role must include),
• Final tips.

Intro:

• Amazon CloudWatch Lambda Insights is a feature designed to provide enhanced operational visibility and monitoring for twtech AWS Lambda functions. 
• Amazon CloudWatch Lambda Insights automatically collects and summarizes:
• System-level metrics, 
• Diagnostic information, 
• Logs into prebuilt dashboards, 
• Which helps in:
•  Troubleshooting,
• Optimizing the performance
• Cost of twtech Lambda functions. 

Key Features and Benefits

• Comprehensive Metrics: It collects detailed system-level metrics beyond standard Lambda metrics, including CPU time, memory usage (utilization and allocation), disk usage, and network performance.
• Automatic Dashboards: It automatically collates and summarizes performance data and logs into ready-to-use dashboards within the CloudWatch console, saving manual setup time.
• Troubleshooting & Optimization: The detailed metrics enable twtech to identify performance bottlenecks, right-size memory allocation to avoid paying for unused capacity, and troubleshoot issues like cold starts or runtime errors.
• Log Analysis: It integrates with CloudWatch Logs Insights, allowing for ad hoc queries and deep analysis of function log data to understand application behavior.
• Multi-Function View: twtech can monitor the performance of multiple Lambda functions simultaneously, filtering by name or tags to track functions belonging to specific applications or stacks. 

Enabling Lambda Insights

twtech can enable Lambda Insights through several methods:

• AWS Management Console: In the Lambda console, navigate to the Configuration tab of twtech function, select Monitoring and operations tools, choose Edit, enable Enhanced monitoring with CloudWatch Lambda Insights, and then Save.
• AWS CLI/CloudFormation/CDK/AWS SAM: For automated deployments and managing multiple functions.
•  twtech can use the AWS Command Line Interface (CLI), AWS CloudFormation, AWS Cloud Development Kit (CDK), or the AWS Serverless Application Model (AWS SAM) by adding a specific layer to its function configuration and ensuring the correct IAM permissions are in place.
• Permissions: The function's execution role must have the necessary permissions, typically by attaching the CloudWatchLambdaInsightsExecutionRolePolicy managed policy. 

NB:

• Lambda Insights only incurs costs for the additional metrics and logs collected.
• twtech pay only for what it uses, as detailed on the Amazon CloudWatch pricing page. 

https://aws.amazon.com/cloudwatch/pricing/

1. The Concept: Lambda Insights

•        CloudWatch Lambda Insights is a monitoring and troubleshooting tool for AWS Lambda.
•        CloudWatch Lambda Insights automatically collects enhanced metrics, performance data, and logs about twtech Lambda functions so it can visualize, debug, and optimize functioning behavior.
•        CloudWatch Lambda Insights goes beyond the default Lambda metrics (invocations, errors, duration, throttles) by providing deep system-level and runtime-level telemetry.

 2. How It Works (Architecture Flow)

1. Lambda Execution Environment
• Lambda function runs inside an AWS-managed execution environment.
• When Lambda Insights is enabled, an AWS Lambda Insights extension is added.
2. CloudWatch Lambda Insights Extension
• Runs inside the execution environment as a sidecar process.
• Collects telemetry:
• System metrics: CPU time, memory usage, network I/O, file system usage.
• Runtime metrics: Cold starts, initialization time, errors, etc.
• Periodically pushes this data to CloudWatch Logs/CloudWatch Metrics.
3. CloudWatch Logs & Metrics
• Enhanced metrics are available in the Lambda Insights dashboard.
• Logs are enriched with structured performance data.
4. Visualization & Alerts
• CloudWatch console provides Lambda Insights dashboards per function.
• Alarms can be created (e.g., memory usage > 90%).
• Logs can be queried with CloudWatch Logs Insights.

 3. Metrics Collected (Beyond Standard Lambda)

Standard Lambda Metrics (default):

• Invocations,  
• Duration, 
• Errors, 
• Throttles, 
• IteratorAge, 
• ConcurrentExecutions.

Enhanced Metrics via Lambda Insights:

• Memory: Max memory used, % of allocated memory.
• CPU: Total CPU time used, context switches.
• Init Duration: Time spent in function initialization (cold start).
• Network I/O: Bytes in/out.
• File System: Temp storage usage (/tmp).
• Errors & Latency: Detailed breakdown (init vs execution).
• Custom metrics: App-level logs can be correlated.

4. Sample Logs Structured Report (Lambda Insights adds):

{

  "report": {

    "requestId": "twtech-123",

    "initDuration": 250.5,

    "duration": 123.4,

    "billedDuration": 200,

    "memorySizeMB": 512,

    "maxMemoryUsedMB": 300,

    "cpuTimeMs": 150,

    "xrayed": true

  }

}

# NB:

• These logs are queryable in CloudWatch Logs Insights.

 5. Enabling Lambda Insights

Option A – Console

• In the Lambda console, enable Enhanced monitoring (CloudWatch Lambda Insights).

Option B – CLI / Infrastructure as Code

• Attach the required IAM policy (CloudWatchLambdaInsightsExecutionRolePolicy) to twtech Lambda’s execution role.
• Lambda Insights extension layer ARN is added automatically by AWS (for supported runtimes).

 6. Integrations

• X-Ray: Combine traces with Lambda Insights metrics for request-level troubleshooting.
• CloudWatch Alarms: Trigger alarms when memory usage approaches limit, or CPU usage spikes.
• Logs Insights: Query detailed logs for anomalies.
• Security/Compliance: Detect abnormal resource usage that could hint at misconfiguration or abuse.

 7. Advanced Use Cases

Right-sizing Functions

•  Compare allocated memory vs max memory used. 
•  Tune memory to save cost or boost performance.

Cold Start Analysis

•  Track init duration trends across invocations. Optimize function startup code.

Troubleshooting Timeouts

•  Correlate CPU/memory/network spikes with function timeouts.

Detecting Resource Leaks

•  /tmp storage usage can reveal functions not cleaning up temp files.

Security Monitoring

•  Unusual network I/O from a Lambda may indicate a compromised function.

Performance Optimization

•  Identify if function is CPU-bound or memory-bound and adjust accordingly.

8. IAM Permissions Needed (The Lambda’s execution role must include):

• CloudWatchLambdaInsightsExecutionRolePolicy

NB:

• The above role provides logs + metrics publishing.

Final tips:

•        Lambda Insights = a profiler + monitoring agent inside Lambda.
•        Lambda Insights is tightly integrated with CloudWatch.
•        Lambda Insights gives twtech system-level + runtime-level observability to optimize cost, performance, and reliability.