title: When is data written to disk if journaling is disabled in WiredTiger storage engine
body: <p>I'm not able to get a clear answer from the <a href="https://docs.mongodb.com/manual/core/journaling/" rel="nofollow noreferrer">docs</a> that when the data is actually persisted to disk in a WiredTiger storage engine when <strong>journaling is disabled</strong>.</p>
  
  <blockquote>
    <p>MongoDB sets checkpoints to occur in WiredTiger on user data at an interval of 60 seconds or when 2 GB of journal data has been written, whichever occurs first.<br><br>
    50 milliseconds since 3.2</p>
  </blockquote>
  
  <p>It also says</p>
  
  <blockquote>
    <p>WiredTiger uses checkpoints to provide a consistent view of data on disk and allow MongoDB to recover from the last checkpoint.</p>
  </blockquote>
  
  <p>But it's not clear at what intervals data is permanently written to disk when I start the server with <strong>journaling disabled</strong>.</p>