title: GitHub Actions - parallel self-hosted runners on the same machine
body: <p>Question related to the topic of <a href="https://github.community/t5/GitHub-Actions/Parallelism-in-Self-Hosted-Runners/td-p/39158" rel="noreferrer">Parallelism in Self-Hosted Runners</a>:</p>
  
  <blockquote>
    <p><em>One self-hosted runner can only run one job at a time, when no available runners are idle, the subsequent jobs will be in queueing until have available runners are idle.</em></p>
  </blockquote>
  
  <p>Can I possibly achieve parallelism by running multiple self-hosted runners <strong>on the same machine with multiple CPUs</strong>?</p>
  
  <p>In the <a href="https://help.github.com/en/actions/getting-started-with-github-actions/about-github-actions#usage-limits" rel="noreferrer">GitHub Actions - Getting Started - Usage Limits</a> I found:</p>
  
  <blockquote>
    <p><em>The number of concurrent jobs you can run in your account depends on your GitHub plan, as indicated in the following table. If exceeded, any additional jobs are queued. <strong>There are no concurrency limits for self-hosted runners.</em></strong></p>
  </blockquote>
  
  <p>But I'm not sure how to understand this in the context of multi-core machines.</p>