https://community.cloudera.com/t5/Support-Questions/Previously-working-spark-jobs-only-now-throwing-quot-java-io/m-p/295919#M218032 <P>Hello&nbsp;<a href="https://community.cloudera.com/t5/user/viewprofilepage/user-id/54172">@rvillanueva</a>&nbsp;,</P><P class="p1">&nbsp;</P><P class="p1">You can check how many threads are used by a user by running ps -L -u &lt;username&gt; | wc -l</P><P class="p1">&nbsp;</P><P class="p1">if the user’s open files&nbsp; limit ( ulimit -n &lt;user name &gt;)&nbsp;is<SPAN class="Apple-converted-space">&nbsp; </SPAN>hit then the user can’t spawn any further more threads. Most&nbsp;possible reasons in this case could be,</P><OL class="ol1"><LI>Same user running other jobs and having open files on the node where it tries to launch/spawn the container.</LI><LI>systems thread might have excluded.</LI><LI>see which application is running and what is their current open files</LI></OL><P>Kindly check application log (<SPAN>application_XXX),if available and see which phase it throw's the exception and on which node the issue is faced.</SPAN></P><P class="p1">&nbsp;</P> Thu, 14 May 2020 10:53:39 GMT Madhur 2020-05-14T10:53:39Z