Guarded rollout errors

Overview

This topic explains how to investigate and debug certain user-facing errors in your guarded rollouts.

When you start a guarded rollout, LaunchDarkly compares the performance of the new variation to the original variation. A regression occurs when sequential testing determines that the absolute difference between the variations represents a statistically significant negative impact on a monitored metric.

If your rollout monitors user-facing error metrics, you can use LaunchDarkly debugging tools to investigate and mitigate the source of errors that contribute to a regression.

Metric availability

The debugging feature is available only for autogenerated metrics with the event key $ld:telemetry:error. LaunchDarkly automatically creates this metric, typically named “User error rate (LaunchDarkly),” although the name may differ depending on your account setup.

This autogenerated metric is available through LaunchDarkly observability SDKs. Enable observability when you initialize the LaunchDarkly client in your app. To learn how, read about LaunchDarkly’s observability SDKs.

After you configure the SDK, add the “User error rate (LaunchDarkly)” metric to your guarded rollout when you create the rollout to use the debugging feature.

View regressions

If a guarded rollout identifies a regression, use the Targeting or Monitoring tabs to review the affected metric and investigate related errors.

1. Navigate to your flag or AI Config and open the Targeting or Monitoring tab.
2. Locate the metric tile for “User error rate (LaunchDarkly)”. If LaunchDarkly identifies a regression for this metric, a “User error rate (LaunchDarkly) regressed” message appears.
3. Click Show errors to expand the list of detected errors.
4. Click the error name to navigate to the related error group.

To learn more about investigating error groups, read View errors.