Time to Review Metric

Definition

The Time to Review Metric measures the time taken from when a pull request (PR) is ready for review (either opened or transitioned out of draft) to when the first review occurs.

Why is This Metric Useful?

• This metric helps teams understand how quickly reviewers begin engaging with new PRs, providing insights into responsiveness and prioritization.

How to Use it?

• Use to balance reviewer workloadUse this metric to identify and balance reviewer workloads.
• Monitor delays in PR reviews to prevent bottlenecks and maintain development flow.

Examples for Context

• Teams that reduced their Time to Review experienced improved overall PR throughput.
• Quick initial reviews contribute to faster feedback cycles and shorter development times.

Data Sources

• PR creation and review events
• Reviewer activity, including first comments or approvals.

Calculation

• For PRs Merged Without a Review:

The metric is calculated as:Time to Review = PR merged at - (PR opened OR draft ended)

• For PRs Merged With a Review:

The metric is calculated as:Time to Review = PR first reviewed at - (PR opened OR draft ended)

This ensures that the metric accounts only for PRs that are fully ready for review and excludes time spent in the draft state.

Tunable Configurations

• Define Reviewer Roles (e.g., internal vs. external) to track specific team dynamics.

Benchmarking Guidance

• First reviews should occur within 24 hours of PR creation.

Error Margins and Limitations

• The metric may not fully account for:
• • Time zone differences among team members.
  • Reviewer availability or unplanned delays.

Stakeholder Use Cases

• Team Leads: Use this metric to balance workloads and identify potential bottlenecks in the review process.
• Reviewers: Monitor and ensure quick responses to new PRs to maintain smooth workflows.