CloudWatch architecture

1. Choose the right signal

You want to chart request latency over time and inspect individual error details.

Which pair fits?

A metric for latency and logs for individual errors.

Metrics summarize numeric measurements. Logs preserve event details. They answer different questions.

The dashboard shows trends and the log stream supplies individual evidence.

Metric: request latency
Log: timestamp, requestId, error detail

2. Make an alarm actionable

One slow request should not page everyone, but sustained latency above your objective should notify the team.

Which alarm design fits?

Choose a latency statistic, threshold, evaluation periods, and notification action.

An alarm needs a meaningful signal and an action. Choose thresholds and periods for the application, not arbitrary universal numbers.

The modeled alarm evaluates sustained degradation and has a response path.

Signal + statistic + threshold + evaluation periods
Action → notification/runbook

3. Investigate before guessing

Latency rises after a deployment. The alarm provides a time window.

What evidence should you correlate first?

Logs, request IDs, metrics, and the deployment timeline for that window.

Use the alarm to narrow the investigation. Correlated evidence is more useful than guessing a cause.

The incident view aligns the affected requests with the deployment.

Time window → affected requests → related errors → deployment change

Practice, then check your understanding

In the interactive tour, make each decision before seeing the outcome. Wrong answers receive coaching, and replay gives you a fresh attempt without duplicating earned XP.

Read the official AWS documentation for service behavior and production details.