Managing AWS Lambda Deep

AWS Lambda Deep Management

Advanced Lambda analysis with optimization recommendations and cost insights.

Phase 1: Discovery

#!/bin/bash
export AWS_PAGER=""

echo "=== Lambda Function Inventory ==="
aws lambda list-functions --output json \
  | jq -r '.Functions[] | "\(.FunctionName)\t\(.Runtime // "container")\t\(.MemorySize)MB\t\(.Timeout)s\t\(.Architectures[0])\t\(.PackageType)\t\(.LastModified)"' \
  | column -t | head -30

echo ""
echo "=== Runtime Distribution ==="
aws lambda list-functions --output text \
  --query 'Functions[].[Runtime]' | sort | uniq -c | sort -rn

echo ""
echo "=== Event Source Mappings ==="
aws lambda list-event-source-mappings --output json \
  | jq -r '.EventSourceMappings[] | "\(.FunctionArn | split(":") | last)\t\(.EventSourceArn | split(":")[2])\t\(.State)\t\(.BatchSize)"' \
  | column -t | head -20

echo ""
echo "=== Layers in Use ==="
aws lambda list-layers --output json \
  | jq -r '.Layers[] | "\(.LayerName)\tv\(.LatestMatchingVersion.Version)\t\(.LatestMatchingVersion.CompatibleRuntimes[0] // "N/A")"' \
  | column -t

Phase 2: Analysis

#!/bin/bash
export AWS_PAGER=""
END=$(date -u +"%Y-%m-%dT%H:%M:%S")
START=$(date -u -d "7 days ago" +"%Y-%m-%dT%H:%M:%S" 2>/dev/null || date -u -v-7d +"%Y-%m-%dT%H:%M:%S")

echo "=== Per-Function Metrics (7d) ==="
for FUNC in $(aws lambda list-functions --query 'Functions[].FunctionName' --output text); do
  {
    INV=$(aws cloudwatch get-metric-statistics --namespace AWS/Lambda --metric-name Invocations \
      --dimensions Name=FunctionName,Value="$FUNC" --start-time "$START" --end-time "$END" \
      --period 604800 --statistics Sum --output text --query 'Datapoints[0].Sum')
    ERR=$(aws cloudwatch get-metric-statistics --namespace AWS/Lambda --metric-name Errors \
      --dimensions Name=FunctionName,Value="$FUNC" --start-time "$START" --end-time "$END" \
      --period 604800 --statistics Sum --output text --query 'Datapoints[0].Sum')
    DUR=$(aws cloudwatch get-metric-statistics --namespace AWS/Lambda --metric-name Duration \
      --dimensions Name=FunctionName,Value="$FUNC" --start-time "$START" --end-time "$END" \
      --period 604800 --statistics Average Maximum --output text --query 'Datapoints[0].[Average,Maximum]')
    THR=$(aws cloudwatch get-metric-statistics --namespace AWS/Lambda --metric-name Throttles \
      --dimensions Name=FunctionName,Value="$FUNC" --start-time "$START" --end-time "$END" \
      --period 604800 --statistics Sum --output text --query 'Datapoints[0].Sum')
    printf "%s\t%s\t%s\t%s\t%s\n" "$FUNC" "${INV:-0}" "${ERR:-0}" "${DUR:-N/A}" "${THR:-0}"
  } &
done
wait

echo ""
echo "=== Dead Letter Queue Config ==="
for FUNC in $(aws lambda list-functions --query 'Functions[].FunctionName' --output text); do
  DLQ=$(aws lambda get-function-configuration --function-name "$FUNC" \
    --query 'DeadLetterConfig.TargetArn' --output text 2>/dev/null)
  [ "$DLQ" != "None" ] && [ -n "$DLQ" ] && echo "$FUNC -> $DLQ"
done

echo ""
echo "=== Provisioned Concurrency ==="
for FUNC in $(aws lambda list-functions --query 'Functions[].FunctionName' --output text); do
  aws lambda list-provisioned-concurrency-configs --function-name "$FUNC" \
    --query "ProvisionedConcurrencyConfigs[].[\"$FUNC\",RequestedProvisionedConcurrentExecutions,AvailableProvisionedConcurrentExecutions,Status]" \
    --output text 2>/dev/null
done | grep -v "^$"

echo ""
echo "=== Account Concurrency Limits ==="
aws lambda get-account-settings --query '{UnreservedConcurrency: AccountLimit.UnreservedConcurrentExecutions, TotalConcurrency: AccountLimit.ConcurrentExecutions}' --output json

Output Format

LAMBDA DEEP ANALYSIS
=====================
Function           Invocations  Errors  Err%    Avg-ms  Max-ms   Throttles  Memory
──────────────────────────────────────────────────────────────────────────────────────
order-processor    45200        12      0.03%   120.4   890.2    0          256MB
auth-handler       128900       450     0.35%   45.2    1200.0   23         128MB
image-resizer      8900         0       0.00%   2400.1  5000.0   0          1024MB

Runtimes: nodejs20.x(5) python3.12(3) java21(1)
Concurrency: 800/1000 unreserved | Provisioned: 2 functions
DLQ configured: 3/9 functions

Safety Rules

• Read-only: Only use list-*, get-*, and CloudWatch get-metric-statistics
• Parallel execution: Use background jobs for multi-function metric queries
• Never invoke functions or modify configurations without explicit confirmation
• Cost awareness: Large accounts may incur CloudWatch API costs with many metric queries

Anti-Hallucination Rules

1. NEVER assume resource names — always discover via CLI/API in Phase 1 before referencing in Phase 2.
2. NEVER fabricate metric names or dimensions — verify against the service documentation or --help output.
3. NEVER mix CLI commands between service versions — confirm which version/API you are targeting.
4. ALWAYS use the discovery → verify → analyze chain — every resource referenced must have been discovered first.
5. ALWAYS handle empty results gracefully — an empty response is valid data, not an error to retry.

Counter-Rationalizations