Monitoring your Merge Queue

Monitor key metrics of your merge queue to optimize throughput and reduce latency, ensuring a streamlined development cycle.


The performance and health of your merge queue are essential for maintaining a productive and efficient development cycle. Monitoring key metrics ensures that you can respond promptly to any bottlenecks, inefficiencies, or potential issues.

Understanding your merge queue’s performance is pivotal for maintaining a robust and streamlined development cycle. Regular monitoring and prompt action based on these metrics can ensure you achieve optimal throughput and latency.

Here’s a guide to the most critical metrics to monitor and how to interpret them.

  1. PRs Merged Per Day: Monitor this metric to ensure your throughput remains stable. Track the number of pull requests merged each day. A consistent trend indicates a stable development environment. Sudden drops or spikes can indicate issues that need attention.

  2. CI Runtime: Keep an eye on CI times to ensure efficiency and timely merges. Monitor the time your Continuous Integration (CI) tests take to run. A sudden increase in runtime can slow down your entire merge queue, delaying other PRs.

  3. Queue Checks Outcome: High success rates indicate a healthy development and review process. It’s essential to ensure that most of the PRs entering the queue get successfully merged. If PRs are frequently removed or fail to merge for any reason, it may signal a need for process refinement or improvement to the CI.

  4. Queue Size: A manageable queue size ensures that PRs don’t stagnate. The number of PRs waiting in the queue should be manageable. If the queue grows significantly or continuously, it indicates a bottleneck or an inefficiency in the process or CI.

  5. Running Checks: A balanced number of running checks ensures you’re utilizing your resources efficiently. Monitor the number of running checks in your queue. If you’re often at full capacity, it might be time to consider adding more speculative checks to increase throughput.

  6. Queue Waiting Time: Reducing waiting time reduces overall latency for your PRs. Track how long PRs spend idle in the queue. Extended idle times increase overall latency and can delay the delivery of features or fixes.

For a visual representation of these metrics, you can refer to the statistics available on the merge queue page of your dashboard. Below are some sample insights:

Statistics page on mergify's dashboard

Datadog

Monitor your merge queues with Mergify Datadog integration.

If our available integrations don’t suit your needs, you have the flexibility to build your own monitoring solution using our API.