Major Description
When a test hangs and is killed by the maven surefire plugin, it tries to capture information about the process to aid in debugging one of those being the dump file.
2020-03-09T02-27-30_920-jvmRun1.dump
maven-surefire-plugin:3.0.0-M1
# Created at 2020-03-09T03:05:40.609 Killing self fork JVM. Received SHUTDOWN command from Maven shutdown hook.
With 3.0.0-M4 it also captures the stack trace as part of the dump file.
maven-surefire-plugin:3.0.0-M4
# Created at 2020-03-09T15:18:40.510
Killing self fork JVM. Received SHUTDOWN command from Maven shutdown hook.
Thread dump before killing the process (45086@hostname):
"Netty IPC Socket Reader #1 for port 59611"
java.lang.Thread.State: RUNNABLE
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.Native.keventWait(Native Method)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.Native.keventWait(Native.java:94)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.KQueueEventLoop.kqueueWait(KQueueEventLoop.java:147)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.KQueueEventLoop.kqueueWait(KQueueEventLoop.java:139)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.KQueueEventLoop.run(KQueueEventLoop.java:208)
at org.apache.hadoop.ipc.shaded.io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:905)
at java.lang.Thread.run(Thread.java:748)
at org.apache.hadoop.ipc.NettyServer$NettyThreadFactory$1.run(NettyServer.java:659)
"Netty IPC Socket Reader #4 for port 59597"
java.lang.Thread.State: RUNNABLE
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.Native.keventWait(Native Method)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.Native.keventWait(Native.java:94)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.KQueueEventLoop.kqueueWait(KQueueEventLoop.java:147)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.KQueueEventLoop.kqueueWait(KQueueEventLoop.java:139)
at org.apache.hadoop.ipc.shaded.io.netty.channel.kqueue.KQueueEventLoop.run(KQueueEventLoop.java:208)
at org.apache.hadoop.ipc.shaded.io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:905)
at java.lang.Thread.run(Thread.java:748)
at org.apache.hadoop.ipc.NettyServer$NettyThreadFactory$1.run(NettyServer.java:659)
"DeletionService #0"
java.lang.Thread.State: WAITING
at sun.misc.Unsafe.park(Native Method)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1081)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1074)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1134)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
...
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Upgrading to a later version will improve debugging hung tests in Tez