TEZ-4388: Asynchttpclient can cause stuck TezChild processes

tez-common/src/main/java/org/apache/tez/util/TezRuntimeShutdownHandler.java

@@ -0,0 +1,44 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * <p/>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p/>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.tez.util;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class TezRuntimeShutdownHandler {
+  private static final Logger LOG = LoggerFactory.getLogger(TezRuntimeShutdownHandler.class);
+
+  private static final List<Runnable> shutdownTasks = new ArrayList<>();
+
+  private TezRuntimeShutdownHandler() {
+  }
+
+  public static void addShutdownTask(Runnable r) {
+    shutdownTasks.add(r);
+  }
+
+  public static synchronized void shutdown() {
+    LOG.info("Handling {} shutdown tasks", shutdownTasks.size());
+    for (Runnable shutdownTask : shutdownTasks) {
+      shutdownTask.run();
+    }
+  }
+}

tez-runtime-internals/src/main/java/org/apache/tez/runtime/task/TezChild.java

@@ -71,6 +71,7 @@
 import org.apache.tez.runtime.api.impl.ExecutionContextImpl;
 import org.apache.tez.runtime.common.objectregistry.ObjectRegistryImpl;
 import org.apache.tez.runtime.internals.api.TaskReporterInterface;
+import org.apache.tez.util.TezRuntimeShutdownHandler;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -390,8 +391,10 @@ public void shutdown() {
       LOG.info("Shutting down container {}", containerIdString);
       // It's possible that there's pending tasks on the executor. Those should be cancelled.
       List<Runnable> pendingRunnables = executor.shutdownNow();
+      LOG.info("There are {} runnables in shared executor, cancelling those...", pendingRunnables.size());
       for (Runnable r : pendingRunnables) {
-        LOG.info("Cancelling pending runnables during TezChild shutdown for containerId={}", containerIdString);
+        LOG.info("Cancelling pending runnable ({}) during TezChild shutdown for containerId={}", r.hashCode(),
+            containerIdString);
         ((FutureTask)r).cancel(false);
       }
       if (taskReporter != null) {
@@ -401,6 +404,8 @@ public void shutdown() {
         RPC.stopProxy(umbilical);
       }
     }
+    TezRuntimeShutdownHandler.shutdown();
+    LOG.info("TezChild shutdown finished");
   }
 
   public static class ContainerExecutionResult {
@@ -522,7 +527,8 @@ public static void main(String[] args) throws IOException, InterruptedException,
         System.getenv(), pid, new ExecutionContextImpl(System.getenv(Environment.NM_HOST.name())),
         credentials, Runtime.getRuntime().maxMemory(), System
             .getenv(ApplicationConstants.Environment.USER.toString()), null, true, hadoopShim);
-    tezChild.run();
+    ContainerExecutionResult result = tezChild.run();
+    LOG.info("TezChild is about to exit from main(), run() returned result: {}", result.toString());
   }
 
   private void handleError(Throwable t) {

tez-runtime-library/src/main/java/org/apache/tez/http/async/netty/AsyncHttpConnection.java

@@ -35,6 +35,7 @@
 import org.apache.tez.runtime.library.common.security.SecureShuffleUtils;
 import org.apache.tez.runtime.library.common.shuffle.orderedgrouped.ShuffleHeader;
 import org.apache.tez.util.StopWatch;
+import org.apache.tez.util.TezRuntimeShutdownHandler;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -102,6 +103,16 @@ private void initClient(HttpConnectionParams httpConnParams) throws IOException
               .build();
           DefaultAsyncHttpClientConfig config = builder.build();
           httpAsyncClient = new DefaultAsyncHttpClient(config);
+          TezRuntimeShutdownHandler.addShutdownTask(() -> {
+            try {
+              if (httpAsyncClient != null) {
+                httpAsyncClient.close();
+                httpAsyncClient = null;
+              }
+            } catch (IOException e) {
+              LOG.warn("Error while closing async client (this won't block shutdown)", e);
+            }
+          });
         }
       }
     }