title: What are the benefits of running multiple Spark tasks in the same JVM?
body: <p>Different sources (e.g. <a href="https://spoddutur.github.io/spark-notes/distribution_of_executors_cores_and_memory_for_spark_application.html" rel="noreferrer">1</a> and  <a href="https://www.slideshare.net/cloudera/top-5-mistakes-to-avoid-when-writing-apache-spark-applications" rel="noreferrer">2</a>) claim that <em>Spark can benefit from running multiple tasks in the same JVM</em>. But they don't explain why.</p>
  
  <p>What are these benefits?</p>