title: java.lang.OutOfMemoryError: unable to create new native thread
body: <p>i saw comment like this</p>
  
  <blockquote>
    <p>one place i have seen this problem is if you keep creating threads, and instead of calling start(), call run() directly on the thread object.
    This will result in the thread object not getting dereferenced...
    So after sometime the message unable to create new native thread comes up</p>
  </blockquote>
  
  <p>on the <a href="http://forums.sun.com/thread.jspa?threadID=5341026" rel="nofollow noreferrer">Sun Java Forums</a></p>
  
  <p>In my application, initialy we plan to use thread, but later, we decided no need anymore, so we just call run() instead of start(). Do we need to do manual GC for new threadClass(..)    ?</p>
  
  <p>my tomcat startup setting</p>
  
  <pre><code>-Xms1024m -Xmx1024m -XX:MaxPermSize=450m 
  </code></pre>