Avoid a double-response to stats

Author: DaveCTurner

server/src/main/java/org/elasticsearch/action/support/ChannelActionListener.java

@@ -8,6 +8,8 @@
 
 package org.elasticsearch.action.support;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.transport.TransportChannel;
 import org.elasticsearch.transport.TransportRequest;
@@ -16,6 +18,8 @@
 public final class ChannelActionListener<
     Response extends TransportResponse, Request extends TransportRequest> implements ActionListener<Response> {
 
+    private static final Logger logger = LogManager.getLogger(ChannelActionListener.class);
+
     private final TransportChannel channel;
     private final Request request;
     private final String actionName;
@@ -31,6 +35,7 @@ public void onResponse(Response response) {
         try {
             channel.sendResponse(response);
         } catch (Exception e) {
+            logger.warn("channel.sendResponse threw exception responding to [" + actionName + "]", e);
             onFailure(e);
         }
     }

server/src/main/java/org/elasticsearch/transport/TcpTransportChannel.java

@@ -8,6 +8,8 @@
 
 package org.elasticsearch.transport;
 
+import org.apache.logging.log4j.message.ParameterizedMessage;
+import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.Version;
 import org.elasticsearch.common.lease.Releasable;
 
@@ -67,7 +69,11 @@ private void release(boolean isExceptionResponse) {
         if (released.compareAndSet(false, true)) {
             assert (releaseBy = new Exception()) != null; // easier to debug if it's already closed
             breakerRelease.close();
+
+            logger.info(new ParameterizedMessage("--> releasing bytes for [{}][{}]", requestId, action), new ElasticsearchException("stack trace"));
+
         } else if (isExceptionResponse == false) {
+            logger.error(new ParameterizedMessage("--> double-relase of bytes for [{}][{}]", requestId, action), new ElasticsearchException("stack trace"));
             // only fail if we are not sending an error - we might send the error triggered by the previous
             // sendResponse call
             throw new IllegalStateException("reserved bytes are already released", releaseBy);

x-pack/plugin/ccr/src/internalClusterTest/java/org/elasticsearch/xpack/ccr/CcrRepositoryIT.java

@@ -604,6 +604,7 @@ public void testCcrRepositoryFailsToFetchSnapshotShardSizes() throws Exception {
                     ) {
                         simulatedFailures.incrementAndGet();
                         channel.sendResponse(new ElasticsearchException("simulated"));
+                        return;
                     }
                 }
                 handler.messageReceived(request, channel, task);