Describe a time when you had to troubleshoot a performance issue in AWS.

Example: Application experiencing high latency. Investigation steps: 1) Check CloudWatch metrics for CPU/memory usage, 2) Analyze ALB access logs for response times, 3) Use X-Ray for distributed tracing, 4) Check database performance with Performance Insights, 5) Identified database connection pooling issue, 6) Implemented connection pooling and added read replicas.