Frequent Jenkins failures due to "Backing channel 'beamN' is disconnected"

[kennknowles]

Example failure below.

https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Spark/3809/console

...
2018-01-02T22:46:30.423 [INFO] Excluding io.grpc:grpc-protobuf-lite:jar:1.2.0 from the shaded jar.
2018-01-02T22:46:30.423 [INFO] Excluding io.grpc:grpc-stub:jar:1.2.0 from the shaded jar.
ERROR: Failed to parse POMs
java.io.IOException: Backing channel 'beam8' is disconnected.
at hudson.remoting.RemoteInvocationHandler.channelOrFail(RemoteInvocationHandler.java:212)
at hudson.remoting.RemoteInvocationHandler.invoke(RemoteInvocationHandler.java:281)
at com.sun.proxy.$Proxy131.isAlive(Unknown Source)
at hudson.Launcher$RemoteLauncher$ProcImpl.isAlive(Launcher.java:1138)
at hudson.maven.ProcessCache$MavenProcess.call(ProcessCache.java:166)
at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.doRun(MavenModuleSetBuild.java:879)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:504)
at hudson.model.Run.execute(Run.java:1724)
at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:543)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:421)
Caused by: java.io.IOException: Unexpected termination of the channel
at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:77)
Caused by: java.io.EOFException
at java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2675)
at java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:3150)
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:859)
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:355)
at hudson.remoting.ObjectInputStreamEx.<init>(ObjectInputStreamEx.java:48)
at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:35)
at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:63)
ERROR: Step ‘E-mail Notification’ failed: no workspace for beam_PostCommit_Java_ValidatesRunner_Spark #3809
ERROR: beam8 is offline; cannot locate JDK 1.8 (latest)
ERROR: beam8 is offline; cannot locate Maven 3.3.3
Finished: FAILURE

Imported from Jira BEAM-3407. Original Jira may contain additional context.
Reported by: herohde.