Running Concurrent Builds with GitLab Runner

Introduction:
In continuous integration (CI) and continuous delivery (CD) pipelines, it’s crucial to optimize build times and resource utilization. GitLab Runner, a component of GitLab CI/CD, offers the flexibility to run concurrent builds, allowing teams to execute multiple pipelines simultaneously. In this blog post, we’ll explore how to configure GitLab Runner to run concurrent builds efficiently.

Understanding Concurrent Builds:
Concurrent builds refer to the ability to execute multiple pipelines or jobs concurrently, thereby reducing overall build times and increasing throughput. By leveraging concurrent builds, teams can improve development velocity and ensure faster feedback loops.

Configuring GitLab Runner for Concurrent Builds:
To enable concurrent builds in GitLab Runner, follow these steps:

1. Install GitLab Runner: First, ensure that GitLab Runner is installed on your build machine. You can install GitLab Runner using the instructions provided in the GitLab documentation.
2. Configure Concurrent Builds: Open the GitLab Runner configuration file (config.toml) located on your build machine. Set the concurrent parameter to specify the maximum number of concurrent builds allowed. For example:

   [[runners]]
     name = "My Runner"
     url = "https://gitlab.com/"
     token = "my-runner-token"
     executor = "shell"
     concurrent = 5  # Maximum 5 concurrent builds

Adjust the value of concurrent based on your infrastructure capacity and requirements.

3. Register Runner: If you haven’t already registered the GitLab Runner with your GitLab instance, use the gitlab-runner register command to register the Runner. Follow the prompts to specify the GitLab instance URL, registration token, and other configuration details.
4. Restart GitLab Runner: After making changes to the GitLab Runner configuration, restart the GitLab Runner service to apply the changes:

   sudo gitlab-runner restart

This command ensures that the GitLab Runner picks up the updated configuration settings.

Benefits of Concurrent Builds:
Enabling concurrent builds with GitLab Runner offers several benefits:

1. Improved Build Times: Concurrent builds allow multiple pipelines or jobs to execute simultaneously, reducing overall build times and providing faster feedback to developers.
2. Resource Optimization: By maximizing resource utilization, concurrent builds ensure efficient use of available infrastructure, leading to better scalability and cost-effectiveness.
3. Increased Throughput: With the ability to handle multiple builds concurrently, teams can achieve higher throughput, enabling them to deliver features and updates more rapidly.

Conclusion:
Running concurrent builds with GitLab Runner is a valuable strategy for optimizing CI/CD pipelines and accelerating software delivery. By configuring GitLab Runner to support concurrent execution, teams can streamline their development processes, enhance productivity, and achieve faster time-to-market.

Take advantage of concurrent builds in GitLab Runner to supercharge your CI/CD workflows and empower your team to deliver high-quality software efficiently.

References:

• GitLab Runner Documentation: https://docs.gitlab.com/runner/
• GitLab CI/CD Documentation: https://docs.gitlab.com/ee/ci/