title: Does OS thread scheduler gets override by JVM?
body: <p>according to the following resources, thread scheduling is done by either operation system or JVM or both. </p>
  
  <p>1.<a href="http://tutorials.jenkov.com/java-concurrency/creating-and-starting-threads.html" rel="nofollow noreferrer">http://tutorials.jenkov.com/java-concurrency/creating-and-starting-threads.html</a></p>
  
  <p>2.<a href="https://www.javatpoint.com/thread-scheduler-in-java" rel="nofollow noreferrer">https://www.javatpoint.com/thread-scheduler-in-java</a></p>
  
  <p><strong>MY QUESTION:</strong></p>
  
  <p>1.who schedules the thread?</p>
  
  <p>2.does the thread scheduler gets overridden anywhere?(like OS thread being overridden by JVM thread scheduler)</p>
  
  <p>3.how do i change from preemptive scheduling to time slicing scheduling ? or vice versa?</p>