ES ClassNotFoundException and others when low memory

gistfile1.txt

New I/O client worker #1-6 03/26 16:26:43 WARN  .elasticsearch.transport.netty  - [Goblyn] Message not fully read (response) for [638] handler org.elasticsearch.action.TransportActionNodeProxy$1@1a06f956, error [true], resetting
SimpleAsyncTaskExecutor-1 03/26 16:26:43 ERROR .AttachmentIndexerErrorHandler  - Error indexing attachment
org.springframework.amqp.rabbit.listener.ListenerExecutionFailedException: Listener method 'handleMessage' threw exception
	at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.invokeListenerMethod(MessageListenerAdapter.java:443)
	at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.onMessage(MessageListenerAdapter.java:344)
	at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:506)
	at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:470)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$001(SimpleMessageListenerContainer.java:56)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$1.invokeListener(SimpleMessageListenerContainer.java:103)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.invokeListener(SimpleMessageListenerContainer.java:560)
	at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:452)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.doReceiveAndExecute(SimpleMessageListenerContainer.java:436)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.receiveAndExecute(SimpleMessageListenerContainer.java:420)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$200(SimpleMessageListenerContainer.java:56)
	at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.run(SimpleMessageListenerContainer.java:505)
	at java.lang.Thread.run(Thread.java:680)
Caused by: org.elasticsearch.transport.TransportSerializationException: Failed to deserialize exception response from stream
	at org.elasticsearch.transport.netty.MessageChannelHandler.handlerResponseError(MessageChannelHandler.java:277)
	at org.elasticsearch.transport.netty.MessageChannelHandler.process(MessageChannelHandler.java:231)
	at org.elasticsearch.transport.netty.MessageChannelHandler.callDecode(MessageChannelHandler.java:141)
	at org.elasticsearch.transport.netty.MessageChannelHandler.messageReceived(MessageChannelHandler.java:93)
	at org.elasticsearch.common.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:75)
	at org.elasticsearch.common.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:558)
	at org.elasticsearch.common.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:553)
	at org.elasticsearch.common.netty.channel.Channels.fireMessageReceived(Channels.java:268)
	at org.elasticsearch.common.netty.channel.Channels.fireMessageReceived(Channels.java:255)
	at org.elasticsearch.common.netty.channel.socket.nio.NioWorker.read(NioWorker.java:343)
	at org.elasticsearch.common.netty.channel.socket.nio.NioWorker.processSelectedKeys(NioWorker.java:274)
	at org.elasticsearch.common.netty.channel.socket.nio.NioWorker.run(NioWorker.java:194)
	at org.elasticsearch.common.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:102)
	at org.elasticsearch.common.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	... 1 more
Caused by: java.io.InvalidClassException: failed to read class descriptor
	at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1566)
	at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1495)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1731)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
	at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1946)
	at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1870)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
	at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1946)
	at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1870)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:350)
	at org.elasticsearch.transport.netty.MessageChannelHandler.handlerResponseError(MessageChannelHandler.java:275)
	... 16 more
Caused by: java.lang.ClassNotFoundException: org.apache.tika.exception.TikaException
	at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
	at org.elasticsearch.common.io.ThrowableObjectInputStream.loadClass(ThrowableObjectInputStream.java:93)
	at org.elasticsearch.common.io.ThrowableObjectInputStream.readClassDescriptor(ThrowableObjectInputStream.java:67)
	at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1564)
	... 29 more