PR Review Time

What is this metric?

The time it takes to complete a code review of a PR before it gets merged.

Why is it important?

Code review should be conducted almost in real-time and usually take less than two days. Abnormally long PR Review Time may indicate one or more of the following problems:

1. The PR size is too large that makes it difficult to review.
2. The team is too busy to review code.

Which dashboard(s) does it exist in?

• Engineering Throughput and Cycle Time
• Engineering Throughput and Cycle Time - Team View

How is it calculated?

This metric is the time frame between when the first comment is added to a PR, to when the PR is merged.

Data Sources Required

This metric relies on PRs/MRs collected from GitHub, GitLab, BitBucket, Gitee or other code review tools.

Data Transformation Required

N/A

SQL Queries

The following SQL shows how to find the review time of a specific PR. DevLake pre-calculates the metric and stores it in table.project_pr_metrics.

SELECT
  pr_review_time/60 as 'PR Review Time(h)'
FROM
  project_pr_metrics

If you want to measure the monthly trend of PR review time in the screenshot below, please run the following SQL in Grafana.

SELECT 
  DATE_ADD(date(pr.created_date), INTERVAL -DAY(date(pr.created_date))+1 DAY) as time,
  avg(ppm.pr_review_time)/60 as 'PR Review Time(h)'
FROM 
  pull_requests pr
  JOIN project_pr_metrics ppm ON pr.id = ppm.id
GROUP BY 1
ORDER BY 1

How to improve?

1. Use DevLake's dashboards to monitor your delivery progress;
2. Use automated tests for the initial work;
3. Reduce PR size;
4. Analyze the causes for long reviews.