[KUDU-1962] NPE and lost callback in Java client when master queue overflows

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.3.0
• Fix Version/s: 1.3.1, 1.4.0
• Component/s: client
• Target Version/s: 1.3.1, 1.4.0
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 30/Mar/17 22:37
• Updated: 31/Mar/17 05:43
• Resolved: 31/Mar/17 05:43

Description

An Impala user reported seeing the following stack trace in the frontend, followed by a query hanging in planning:

	
Mar 30, 2017 2:14:32 AM org.apache.kudu.client.shaded.org.jboss.netty.util.HashedWheelTimer
WARNING: An exception was thrown by TimerTask.
java.lang.NullPointerException
at org.apache.kudu.client.AsyncKuduClient.sendRpcToTablet(AsyncKuduClient.java:737)
at org.apache.kudu.client.AsyncKuduClient$2RetryTimer.run(AsyncKuduClient.java:1297)
at org.apache.kudu.client.shaded.org.jboss.netty.util.HashedWheelTimer$HashedWheelTimeout.expire(HashedWheelTimer.java:556)
at org.apache.kudu.client.shaded.org.jboss.netty.util.HashedWheelTimer$HashedWheelBucket.expireTimeouts(HashedWheelTimer.java:632)
at org.apache.kudu.client.shaded.org.jboss.netty.util.HashedWheelTimer$Worker.run(HashedWheelTimer.java:369)
at org.apache.kudu.client.shaded.org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)
at java.lang.Thread.run(Thread.java:745)