Guarded rollouts

Overview

This topic explains how to monitor metrics on flag and AI Config releases and configure LaunchDarkly to take action on the results.

When you begin serving a new flag or AI Config variation, such as when you toggle a flag on or update the default rule variation, you can add a guarded rollout. A guarded rollout progressively increases traffic to the new variation while monitoring selected metrics for regressions until the rollout reaches 100%. If LaunchDarkly detects a regression before the rollout reaches 100%, it can pause the rollout and sends a notification.

In a guarded rollout, each metric appears in its own tile. Each tile includes a difference chart that shows how the new variation compares to the original variation over time. The dark grey line represents the absolute difference, and the shaded grey area represents the absolute difference’s confidence interval.

LaunchDarkly identifies a regression when sequential testing determines that the absolute difference represents a statistically significant negative impact on a monitored metric.

On the chart, this occurs when the confidence interval falls entirely on the side of worse performance based on the metric’s success criteria. For lower-is-better metrics, the confidence interval lies above zero. For higher-is-better metrics, the confidence interval lies below zero.

When a regression is detected, the metric tile highlights the regression. If automatic rollback is enabled, LaunchDarkly also rolls back the release.

Guarded rollouts are one of several options that LaunchDarkly provides to help you release features safely and gradually. To learn about other release options, read Releasing features with LaunchDarkly.

You can create a guarded rollout on any targeting rule, as long as no other guarded rollouts, progressive rollouts, or experiments are running on the flag or AI Config, and the flag is not a migration flag.

View flags with guarded rollouts

To view flags that currently use or previously used a guarded rollout, click Guarded rollouts in the left navigation.

Use the Filters menu to filter the list by rollout status. Navigate to the flag’s Monitoring tab to view and manage the rollout.

AI Configs with guarded rollouts do not appear on the Guarded rollouts list.

Metrics and guarded rollouts

Metrics track system health indicators and end-user behavior, such as errors, latencies, clicks, and conversions. When you attach metrics to a flag or AI Config change, you can measure how the new variation affects those metrics during the rollout.

You can connect metrics to LaunchDarkly in several ways:

• Use one of our metrics integrations.
• Call the metric import API.
• Use a LaunchDarkly SDK to send custom events and connect them to metrics.
• Enable OpenTelemetry in a LaunchDarkly SDK and send traces to LaunchDarkly to autogenerate metrics.

To learn more, read Metrics.

Regressions

When you attach metrics to a flag or AI Config and start a guarded rollout, LaunchDarkly compares the performance of the new variation to the original variation.

A regression is a statistically significant negative impact on a monitored metric. Release Guardian determines this by measuring the absolute difference between the new and original variations and applying sequential testing.

You can configure LaunchDarkly to notify you of a regression, or to notify you and automatically roll back the release when a regression is identified.

To learn how to investigate regressions in your guarded rollouts, read Guarded rollout errors.