MAPREDUCE-5044. Have AM trigger jstack on task attempts that timeout before killing them. (Eric Payne and Gera Shegalov via mingma)

(cherry picked from commit 4a1cedc010d3fa1d8ef3f2773ca12acadfee5ba5)

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapred/LocalContainerLauncher.java

@@ -20,6 +20,10 @@ package org.apache.hadoop.mapred;
 
 import java.io.File;
 import java.io.IOException;
+import java.lang.management.ManagementFactory;
+import java.lang.management.RuntimeMXBean;
+import java.lang.management.ThreadInfo;
+import java.lang.management.ThreadMXBean;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
@@ -255,6 +259,30 @@ public class LocalContainerLauncher extends AbstractService implements
 
         } else if (event.getType() == EventType.CONTAINER_REMOTE_CLEANUP) {
 
+          if (event.getDumpContainerThreads()) {
+            try {
+              // Construct full thread dump header
+              System.out.println(new java.util.Date());
+              RuntimeMXBean rtBean = ManagementFactory.getRuntimeMXBean();
+              System.out.println("Full thread dump " + rtBean.getVmName()
+                  + " (" + rtBean.getVmVersion()
+                  + " " + rtBean.getSystemProperties().get("java.vm.info")
+                  + "):\n");
+              // Dump threads' states and stacks
+              ThreadMXBean tmxBean = ManagementFactory.getThreadMXBean();
+              ThreadInfo[] tInfos = tmxBean.dumpAllThreads(
+                  tmxBean.isObjectMonitorUsageSupported(),
+                  tmxBean.isSynchronizerUsageSupported());
+              for (ThreadInfo ti : tInfos) {
+                System.out.println(ti.toString());
+              }
+            } catch (Throwable t) {
+              // Failure to dump stack shouldn't cause method failure.
+              System.out.println("Could not create full thread dump: "
+                  + t.getMessage());
+            }
+          }
+
           // cancel (and interrupt) the current running task associated with the
           // event
           TaskAttemptId taId = event.getTaskAttemptID();

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/job/impl/TaskAttemptImpl.java

@@ -2175,7 +2175,8 @@ public abstract class TaskAttemptImpl implements
         taskAttempt.container.getId(), StringInterner
         .weakIntern(taskAttempt.container.getNodeId().toString()),
         taskAttempt.container.getContainerToken(),
-        ContainerLauncher.EventType.CONTAINER_REMOTE_CLEANUP));
+        ContainerLauncher.EventType.CONTAINER_REMOTE_CLEANUP,
+        event.getType() == TaskAttemptEventType.TA_TIMED_OUT));
   }
 
   /**

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/launcher/ContainerLauncherEvent.java

@@ -30,17 +30,29 @@ public class ContainerLauncherEvent
   private ContainerId containerID;
   private String containerMgrAddress;
   private Token containerToken;
+  private boolean dumpContainerThreads;
 
   public ContainerLauncherEvent(TaskAttemptId taskAttemptID, 
       ContainerId containerID,
       String containerMgrAddress,
       Token containerToken,
       ContainerLauncher.EventType type) {
+    this(taskAttemptID, containerID, containerMgrAddress, containerToken, type,
+        false);
+  }
+
+  public ContainerLauncherEvent(TaskAttemptId taskAttemptID,
+      ContainerId containerID,
+      String containerMgrAddress,
+      Token containerToken,
+      ContainerLauncher.EventType type,
+      boolean dumpContainerThreads) {
     super(type);
     this.taskAttemptID = taskAttemptID;
     this.containerID = containerID;
     this.containerMgrAddress = containerMgrAddress;
     this.containerToken = containerToken;
+    this.dumpContainerThreads = dumpContainerThreads;
   }
 
   public TaskAttemptId getTaskAttemptID() {
@@ -59,6 +71,10 @@ public class ContainerLauncherEvent
     return containerToken;
   }
 
+  public boolean getDumpContainerThreads() {
+    return dumpContainerThreads;
+  }
+
   @Override
   public String toString() {
     return super.toString() + " for container " + containerID + " taskAttempt "
@@ -77,6 +93,8 @@ public class ContainerLauncherEvent
         + ((containerToken == null) ? 0 : containerToken.hashCode());
     result = prime * result
         + ((taskAttemptID == null) ? 0 : taskAttemptID.hashCode());
+    result = prime * result
+        + (dumpContainerThreads ? 1 : 0);
     return result;
   }
 
@@ -109,7 +127,8 @@ public class ContainerLauncherEvent
         return false;
     } else if (!taskAttemptID.equals(other.taskAttemptID))
       return false;
-    return true;
+
+    return dumpContainerThreads == other.dumpContainerThreads;
   }
 
 }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/launcher/ContainerLauncherImpl.java

@@ -46,6 +46,7 @@ import org.apache.hadoop.mapreduce.v2.app.job.event.TaskAttemptEventType;
 import org.apache.hadoop.service.AbstractService;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.util.concurrent.HadoopThreadPoolExecutor;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -53,6 +54,7 @@ import org.apache.hadoop.yarn.api.protocolrecords.StopContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersResponse;
 import org.apache.hadoop.yarn.api.records.ContainerId;
 import org.apache.hadoop.yarn.api.records.ContainerLaunchContext;
+import org.apache.hadoop.yarn.api.records.SignalContainerCommand;
 import org.apache.hadoop.yarn.client.api.impl.ContainerManagementProtocolProxy;
 import org.apache.hadoop.yarn.client.api.impl.ContainerManagementProtocolProxy.ContainerManagementProtocolProxyData;
 import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
@@ -191,9 +193,13 @@ public class ContainerLauncherImpl extends AbstractService implements
         }
       }
     }
-    
+
+    public void kill() {
+      kill(false);
+    }
+
     @SuppressWarnings("unchecked")
-    public synchronized void kill() {
+    public synchronized void kill(boolean dumpThreads) {
 
       if(this.state == ContainerState.PREP) {
         this.state = ContainerState.KILLED_BEFORE_LAUNCH;
@@ -204,6 +210,13 @@ public class ContainerLauncherImpl extends AbstractService implements
         try {
           proxy = getCMProxy(this.containerMgrAddress, this.containerID);
 
+          if (dumpThreads) {
+            final SignalContainerRequest request = SignalContainerRequest
+                .newInstance(containerID,
+                    SignalContainerCommand.OUTPUT_THREAD_DUMP);
+            proxy.getContainerManagementProtocol().signalToContainer(request);
+          }
+
           // kill the remote container if already launched
           List<ContainerId> ids = new ArrayList<ContainerId>();
           ids.add(this.containerID);
@@ -381,7 +394,7 @@ public class ContainerLauncherImpl extends AbstractService implements
         break;
 
       case CONTAINER_REMOTE_CLEANUP:
-        c.kill();
+        c.kill(event.getDumpContainerThreads());
         break;
 
       case CONTAINER_COMPLETED:

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/test/java/org/apache/hadoop/mapreduce/v2/app/launcher/TestContainerLauncher.java

@@ -33,7 +33,6 @@ import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.junit.Assert;
-
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
@@ -58,6 +57,8 @@ import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.yarn.api.ContainerManagementProtocol;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -73,6 +74,7 @@ import org.apache.hadoop.yarn.api.records.Token;
 import org.apache.hadoop.yarn.client.api.impl.ContainerManagementProtocolProxy;
 import org.apache.hadoop.yarn.client.api.impl.ContainerManagementProtocolProxy.ContainerManagementProtocolProxyData;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.exceptions.YarnException;
 import org.apache.hadoop.yarn.factories.RecordFactory;
 import org.apache.hadoop.yarn.factory.providers.RecordFactoryProvider;
 import org.apache.hadoop.yarn.ipc.HadoopYarnProtoRPC;
@@ -460,5 +462,11 @@ public class TestContainerLauncher {
           "Dummy function cause"));
       throw new IOException(e);
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException, IOException {
+      return null;
+    }
   }
 }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/test/java/org/apache/hadoop/mapreduce/v2/app/launcher/TestContainerLauncherImpl.java

@@ -50,6 +50,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequ
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersRequest;
@@ -465,6 +467,12 @@ public class TestContainerLauncherImpl {
     @Override
     public void close() throws IOException {
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException, IOException {
+      return null;
+    }
   }
   
   @SuppressWarnings("serial")

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/main/java/org/apache/hadoop/mapred/ResourceMgrDelegate.java

@@ -496,8 +496,9 @@ public class ResourceMgrDelegate extends YarnClient {
   }
 
   @Override
-  public void signalContainer(ContainerId containerId, SignalContainerCommand command)
+  public void signalToContainer(ContainerId containerId,
+      SignalContainerCommand command)
       throws YarnException, IOException {
-    client.signalContainer(containerId, command);
+    client.signalToContainer(containerId, command);
   }
 }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapred/TestClientRedirect.java

@@ -481,7 +481,7 @@ public class TestClientRedirect {
     }
 
     @Override
-    public SignalContainerResponse signalContainer(
+    public SignalContainerResponse signalToContainer(
         SignalContainerRequest request) throws IOException {
       return null;
     }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/mapreduce/v2/TestMRJobs.java

@@ -24,6 +24,7 @@ import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.InputStreamReader;
 import java.io.StringReader;
 import java.net.URI;
 import java.security.PrivilegedExceptionAction;
@@ -980,6 +981,124 @@ public class TestMRJobs {
     _testDistributedCache(remoteJobJarPath.toUri().toString());
   }
 
+  @Test(timeout = 120000)
+  public void testThreadDumpOnTaskTimeout() throws IOException,
+      InterruptedException, ClassNotFoundException {
+    if (!(new File(MiniMRYarnCluster.APPJAR)).exists()) {
+      LOG.info("MRAppJar " + MiniMRYarnCluster.APPJAR
+          + " not found. Not running test.");
+      return;
+    }
+
+    final SleepJob sleepJob = new SleepJob();
+    final JobConf sleepConf = new JobConf(mrCluster.getConfig());
+    sleepConf.setLong(MRJobConfig.TASK_TIMEOUT, 3 * 1000L);
+    sleepConf.setInt(MRJobConfig.MAP_MAX_ATTEMPTS, 1);
+    sleepJob.setConf(sleepConf);
+    if (this instanceof TestUberAM) {
+      sleepConf.setInt(MRJobConfig.MR_AM_TO_RM_HEARTBEAT_INTERVAL_MS,
+          30 * 1000);
+    }
+    // sleep for 10 seconds to trigger a kill with thread dump
+    final Job job = sleepJob.createJob(1, 0, 10 * 60 * 1000L, 1, 0L, 0);
+    job.setJarByClass(SleepJob.class);
+    job.addFileToClassPath(APP_JAR); // The AppMaster jar itself.
+    job.waitForCompletion(true);
+    final JobId jobId = TypeConverter.toYarn(job.getJobID());
+    final ApplicationId appID = jobId.getAppId();
+    int pollElapsed = 0;
+    while (true) {
+      Thread.sleep(1000);
+      pollElapsed += 1000;
+      if (TERMINAL_RM_APP_STATES.contains(mrCluster.getResourceManager()
+          .getRMContext().getRMApps().get(appID).getState())) {
+        break;
+      }
+      if (pollElapsed >= 60000) {
+        LOG.warn("application did not reach terminal state within 60 seconds");
+        break;
+      }
+    }
+
+    // Job finished, verify logs
+    //
+
+    final String appIdStr = appID.toString();
+    final String appIdSuffix = appIdStr.substring("application_".length(),
+        appIdStr.length());
+    final String containerGlob = "container_" + appIdSuffix + "_*_*";
+    final String syslogGlob = appIdStr
+        + Path.SEPARATOR + containerGlob
+        + Path.SEPARATOR + TaskLog.LogName.SYSLOG;
+    int numAppMasters = 0;
+    int numMapTasks = 0;
+
+    for (int i = 0; i < NUM_NODE_MGRS; i++) {
+      final Configuration nmConf = mrCluster.getNodeManager(i).getConfig();
+      for (String logDir :
+               nmConf.getTrimmedStrings(YarnConfiguration.NM_LOG_DIRS)) {
+        final Path absSyslogGlob =
+            new Path(logDir + Path.SEPARATOR + syslogGlob);
+        LOG.info("Checking for glob: " + absSyslogGlob);
+        for (FileStatus syslog : localFs.globStatus(absSyslogGlob)) {
+          boolean foundAppMaster = false;
+          boolean foundThreadDump = false;
+
+          // Determine the container type
+          final BufferedReader syslogReader = new BufferedReader(
+              new InputStreamReader(localFs.open(syslog.getPath())));
+          try {
+            for (String line; (line = syslogReader.readLine()) != null; ) {
+              if (line.contains(MRAppMaster.class.getName())) {
+                foundAppMaster = true;
+                break;
+              }
+            }
+          } finally {
+            syslogReader.close();
+          }
+
+          // Check for thread dump in stdout
+          final Path stdoutPath = new Path(syslog.getPath().getParent(),
+              TaskLog.LogName.STDOUT.toString());
+          final BufferedReader stdoutReader = new BufferedReader(
+              new InputStreamReader(localFs.open(stdoutPath)));
+          try {
+            for (String line; (line = stdoutReader.readLine()) != null; ) {
+              if (line.contains("Full thread dump")) {
+                foundThreadDump = true;
+                break;
+              }
+            }
+          } finally {
+            stdoutReader.close();
+          }
+
+          if (foundAppMaster) {
+            numAppMasters++;
+            if (this instanceof TestUberAM) {
+              Assert.assertTrue("No thread dump", foundThreadDump);
+            } else {
+              Assert.assertFalse("Unexpected thread dump", foundThreadDump);
+            }
+          } else {
+            numMapTasks++;
+            Assert.assertTrue("No thread dump", foundThreadDump);
+          }
+        }
+      }
+    }
+
+    // Make sure we checked non-empty set
+    //
+    Assert.assertEquals("No AppMaster log found!", 1, numAppMasters);
+    if (sleepConf.getBoolean(MRJobConfig.JOB_UBERTASK_ENABLE, false)) {
+      Assert.assertSame("MapTask log with uber found!", 0, numMapTasks);
+    } else {
+      Assert.assertSame("No MapTask log found!", 1, numMapTasks);
+    }
+  }
+
   private Path createTempFile(String filename, String contents)
       throws IOException {
     Path path = new Path(TEST_ROOT_DIR, filename);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/api/ApplicationClientProtocol.java

@@ -563,7 +563,7 @@ public interface ApplicationClientProtocol extends ApplicationBaseProtocol {
    */
   @Public
   @Unstable
-  public SignalContainerResponse signalContainer(
+  SignalContainerResponse signalToContainer(
       SignalContainerRequest request) throws YarnException,
       IOException;
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/api/ContainerManagementProtocol.java

@@ -27,6 +27,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequ
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -194,4 +196,7 @@ public interface ContainerManagementProtocol {
   IncreaseContainersResourceResponse increaseContainersResource(
       IncreaseContainersResourceRequest request) throws YarnException,
       IOException;
+
+  SignalContainerResponse signalToContainer(SignalContainerRequest request)
+      throws YarnException, IOException;
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/api/protocolrecords/SignalContainerResponse.java

@@ -28,7 +28,7 @@ import org.apache.hadoop.yarn.api.ApplicationClientProtocol;
  *
  * <p>Currently it's empty.</p>
  *
- * @see ApplicationClientProtocol#signalContainer(SignalContainerRequest)
+ * @see ApplicationClientProtocol#signalToContainer(SignalContainerRequest)
  */
 @Public
 @Evolving

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/proto/applicationclient_protocol.proto

@@ -59,5 +59,5 @@ service ApplicationClientProtocolService {
   rpc getLabelsToNodes (GetLabelsToNodesRequestProto) returns (GetLabelsToNodesResponseProto);
   rpc getClusterNodeLabels (GetClusterNodeLabelsRequestProto) returns (GetClusterNodeLabelsResponseProto);
   rpc updateApplicationPriority (UpdateApplicationPriorityRequestProto) returns (UpdateApplicationPriorityResponseProto);
-  rpc signalContainer(SignalContainerRequestProto) returns (SignalContainerResponseProto);
+  rpc signalToContainer(SignalContainerRequestProto) returns (SignalContainerResponseProto);
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/proto/containermanagement_protocol.proto

@@ -35,4 +35,5 @@ service ContainerManagementProtocolService {
   rpc stopContainers(StopContainersRequestProto) returns (StopContainersResponseProto);
   rpc getContainerStatuses(GetContainerStatusesRequestProto) returns (GetContainerStatusesResponseProto);
   rpc increaseContainersResource(IncreaseContainersResourceRequestProto) returns (IncreaseContainersResourceResponseProto);
+  rpc signalToContainer(SignalContainerRequestProto) returns (SignalContainerResponseProto);
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/api/YarnClient.java

@@ -777,6 +777,6 @@ public abstract class YarnClient extends AbstractService {
    * @throws YarnException
    * @throws IOException
    */
-  public abstract void signalContainer(ContainerId containerId,
+  public abstract void signalToContainer(ContainerId containerId,
       SignalContainerCommand command) throws YarnException, IOException;
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/api/impl/YarnClientImpl.java

@@ -858,12 +858,12 @@ public class YarnClientImpl extends YarnClient {
   }
 
   @Override
-  public void signalContainer(ContainerId containerId,
+  public void signalToContainer(ContainerId containerId,
       SignalContainerCommand command)
           throws YarnException, IOException {
     LOG.info("Signalling container " + containerId + " with command " + command);
     SignalContainerRequest request =
         SignalContainerRequest.newInstance(containerId, command);
-    rmClient.signalContainer(request);
+    rmClient.signalToContainer(request);
   }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/ApplicationCLI.java

@@ -284,7 +284,7 @@ public class ApplicationCLI extends YarnCLI {
       if (signalArgs.length == 2) {
         command = SignalContainerCommand.valueOf(signalArgs[1]);
       }
-      signalContainer(containerId, command);
+      signalToContainer(containerId, command);
     } else {
       syserr.println("Invalid Command Usage : ");
       printUsage(title, opts);
@@ -299,11 +299,11 @@ public class ApplicationCLI extends YarnCLI {
    * @param command the signal command
    * @throws YarnException
    */
-  private void signalContainer(String containerIdStr,
+  private void signalToContainer(String containerIdStr,
       SignalContainerCommand command) throws YarnException, IOException {
     ContainerId containerId = ConverterUtils.toContainerId(containerIdStr);
     sysout.println("Signalling container " + containerIdStr);
-    client.signalContainer(containerId, command);
+    client.signalToContainer(containerId, command);
   }
 
   /**

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/test/java/org/apache/hadoop/yarn/client/api/impl/TestYarnClient.java

@@ -1689,11 +1689,11 @@ public class TestYarnClient {
         applicationId, 1);
     ContainerId containerId = ContainerId.newContainerId(appAttemptId, 1);
     SignalContainerCommand command = SignalContainerCommand.OUTPUT_THREAD_DUMP;
-    client.signalContainer(containerId, command);
+    client.signalToContainer(containerId, command);
     final ArgumentCaptor<SignalContainerRequest> signalReqCaptor =
         ArgumentCaptor.forClass(SignalContainerRequest.class);
     verify(((MockYarnClient) client).getRMClient())
-        .signalContainer(signalReqCaptor.capture());
+        .signalToContainer(signalReqCaptor.capture());
     SignalContainerRequest request = signalReqCaptor.getValue();
     Assert.assertEquals(containerId, request.getContainerId());
     Assert.assertEquals(command, request.getCommand());

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/api/ContainerManagementProtocolPB.java

@@ -21,6 +21,11 @@ import org.apache.hadoop.classification.InterfaceAudience.Private;
 import org.apache.hadoop.classification.InterfaceStability.Unstable;
 import org.apache.hadoop.ipc.ProtocolInfo;
 import org.apache.hadoop.yarn.proto.ContainerManagementProtocol.ContainerManagementProtocolService;
+import org.apache.hadoop.yarn.proto.YarnServiceProtos.SignalContainerRequestProto;
+import org.apache.hadoop.yarn.proto.YarnServiceProtos.SignalContainerResponseProto;
+
+import com.google.protobuf.RpcController;
+import com.google.protobuf.ServiceException;
 
 @Private
 @Unstable
@@ -29,4 +34,6 @@ import org.apache.hadoop.yarn.proto.ContainerManagementProtocol.ContainerManagem
     protocolVersion = 1)
 public interface ContainerManagementProtocolPB extends ContainerManagementProtocolService.BlockingInterface {
 
+  SignalContainerResponseProto signalToContainer(RpcController arg0,
+      SignalContainerRequestProto proto) throws ServiceException;
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/api/impl/pb/client/ApplicationClientProtocolPBClientImpl.java

@@ -588,13 +588,13 @@ public class ApplicationClientProtocolPBClientImpl implements ApplicationClientP
   }
 
   @Override
-  public SignalContainerResponse signalContainer(
+  public SignalContainerResponse signalToContainer(
       SignalContainerRequest request) throws YarnException, IOException {
     YarnServiceProtos.SignalContainerRequestProto requestProto =
         ((SignalContainerRequestPBImpl) request).getProto();
     try {
       return new SignalContainerResponsePBImpl(
-          proxy.signalContainer(null, requestProto));
+          proxy.signalToContainer(null, requestProto));
     } catch (ServiceException e) {
       RPCUtil.unwrapAndThrowException(e);
       return null;

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/api/impl/pb/client/ContainerManagementProtocolPBClientImpl.java

@@ -34,6 +34,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequ
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersRequest;
@@ -42,6 +44,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.IncreaseContainersReso
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.IncreaseContainersResourceResponsePBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.GetContainerStatusesRequestPBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.GetContainerStatusesResponsePBImpl;
+import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.SignalContainerRequestPBImpl;
+import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.SignalContainerResponsePBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.StartContainersRequestPBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.StartContainersResponsePBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.StopContainersRequestPBImpl;
@@ -50,6 +54,7 @@ import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.YarnException;
 import org.apache.hadoop.yarn.ipc.RPCUtil;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.GetContainerStatusesRequestProto;
+import org.apache.hadoop.yarn.proto.YarnServiceProtos.SignalContainerRequestProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.StartContainersRequestProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.StopContainersRequestProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.IncreaseContainersResourceRequestProto;
@@ -148,4 +153,18 @@ public class ContainerManagementProtocolPBClientImpl implements ContainerManagem
       return null;
     }
   }
+
+  @Override
+  public SignalContainerResponse signalToContainer(
+      SignalContainerRequest request) throws YarnException, IOException {
+    SignalContainerRequestProto requestProto =
+        ((SignalContainerRequestPBImpl) request).getProto();
+    try {
+      return new SignalContainerResponsePBImpl(
+          proxy.signalToContainer(null, requestProto));
+    } catch (ServiceException e) {
+      RPCUtil.unwrapAndThrowException(e);
+      return null;
+    }
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/api/impl/pb/service/ApplicationClientProtocolPBServiceImpl.java

@@ -596,11 +596,12 @@ public class ApplicationClientProtocolPBServiceImpl implements ApplicationClient
   }
 
   @Override
-  public SignalContainerResponseProto signalContainer(RpcController controller,
+  public SignalContainerResponseProto signalToContainer(
+      RpcController controller,
       YarnServiceProtos.SignalContainerRequestProto proto) throws ServiceException {
     SignalContainerRequestPBImpl request = new SignalContainerRequestPBImpl(proto);
     try {
-      SignalContainerResponse response = real.signalContainer(request);
+      SignalContainerResponse response = real.signalToContainer(request);
       return ((SignalContainerResponsePBImpl)response).getProto();
     } catch (YarnException e) {
       throw new ServiceException(e);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/api/impl/pb/service/ContainerManagementProtocolPBServiceImpl.java

@@ -25,12 +25,15 @@ import org.apache.hadoop.yarn.api.ContainerManagementProtocol;
 import org.apache.hadoop.yarn.api.ContainerManagementProtocolPB;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.IncreaseContainersResourceRequestPBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.IncreaseContainersResourceResponsePBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.GetContainerStatusesRequestPBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.GetContainerStatusesResponsePBImpl;
+import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.SignalContainerRequestPBImpl;
+import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.SignalContainerResponsePBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.StartContainersRequestPBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.StartContainersResponsePBImpl;
 import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.StopContainersRequestPBImpl;
@@ -40,6 +43,8 @@ import org.apache.hadoop.yarn.proto.YarnServiceProtos.IncreaseContainersResource
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.IncreaseContainersResourceResponseProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.GetContainerStatusesRequestProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.GetContainerStatusesResponseProto;
+import org.apache.hadoop.yarn.proto.YarnServiceProtos.SignalContainerRequestProto;
+import org.apache.hadoop.yarn.proto.YarnServiceProtos.SignalContainerResponseProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.StartContainersRequestProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.StartContainersResponseProto;
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.StopContainersRequestProto;
@@ -116,4 +121,19 @@ public class ContainerManagementProtocolPBServiceImpl implements ContainerManage
       throw new ServiceException(e);
     }
   }
+
+  @Override
+  public SignalContainerResponseProto signalToContainer(RpcController arg0,
+      SignalContainerRequestProto proto) throws ServiceException {
+    final SignalContainerRequestPBImpl request =
+        new SignalContainerRequestPBImpl(proto);
+    try {
+      final SignalContainerResponse response = real.signalToContainer(request);
+      return ((SignalContainerResponsePBImpl)response).getProto();
+    } catch (YarnException e) {
+      throw new ServiceException(e);
+    } catch (IOException e) {
+      throw new ServiceException(e);
+    }
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/TestContainerLaunchRPC.java

@@ -35,6 +35,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequ
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -174,5 +176,13 @@ public class TestContainerLaunchRPC {
         IncreaseContainersResourceRequest request) throws YarnException, IOException {
       return null;
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException, IOException {
+      final Exception e = new Exception("Dummy function", new Exception(
+          "Dummy function cause"));
+      throw new YarnException(e);
+    }
   }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/TestContainerResourceIncreaseRPC.java

@@ -29,6 +29,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersRequest;
@@ -158,5 +160,11 @@ public class TestContainerResourceIncreaseRPC {
       }
       throw new YarnException("Shouldn't happen!!");
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException, IOException {
+      return null;
+    }
   }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/TestRPC.java

@@ -38,6 +38,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResp
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetNewApplicationRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -227,6 +229,14 @@ public class TestRPC {
         IncreaseContainersResourceRequest request) throws YarnException, IOException {
       return null;
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException {
+      final Exception e = new Exception(EXCEPTION_MSG,
+          new Exception(EXCEPTION_CAUSE));
+      throw new YarnException(e);
+    }
   }
 
   public static ContainerTokenIdentifier newContainerTokenIdentifier(

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/ContainerManagerImpl.java

@@ -60,11 +60,13 @@ import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.impl.pb.SignalContainerResponsePBImpl;
 import org.apache.hadoop.yarn.api.records.ApplicationAccessType;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.ContainerExitStatus;
@@ -147,6 +149,7 @@ import org.apache.hadoop.yarn.server.utils.YarnServerSecurityUtils;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.protobuf.ByteString;
+
 import org.apache.hadoop.yarn.util.resource.Resources;
 
 public class ContainerManagerImpl extends CompositeService implements
@@ -1380,16 +1383,7 @@ public class ContainerManagerImpl extends CompositeService implements
           (CMgrSignalContainersEvent) event;
       for (SignalContainerRequest request : containersSignalEvent
           .getContainersToSignal()) {
-        ContainerId containerId = request.getContainerId();
-        Container container = this.context.getContainers().get(containerId);
-        if (container != null) {
-          LOG.info(containerId + " signal request by ResourceManager.");
-          this.dispatcher.getEventHandler().handle(
-              new SignalContainersLauncherEvent(container,
-                  request.getCommand()));
-        } else {
-          LOG.info("Container " + containerId + " no longer exists");
-        }
+        internalSignalToContainer(request, "ResourceManager");
       }
       break;
     default:
@@ -1440,4 +1434,28 @@ public class ContainerManagerImpl extends CompositeService implements
   public void updateQueuingLimit(ContainerQueuingLimit queuingLimit) {
     LOG.trace("Implementation does not support queuing of Containers !!");
   }
+
+  @SuppressWarnings("unchecked")
+  @Override
+  public SignalContainerResponse signalToContainer(
+      SignalContainerRequest request) throws YarnException, IOException {
+    internalSignalToContainer(request, "Application Master");
+    return new SignalContainerResponsePBImpl();
+  }
+
+  @SuppressWarnings("unchecked")
+  private void internalSignalToContainer(SignalContainerRequest request,
+      String sentBy) {
+    ContainerId containerId = request.getContainerId();
+    Container container = this.context.getContainers().get(containerId);
+    if (container != null) {
+      LOG.info(containerId + " signal request " + request.getCommand()
+            + " by " + sentBy);
+      this.dispatcher.getEventHandler().handle(
+          new SignalContainersLauncherEvent(container,
+              request.getCommand()));
+    } else {
+      LOG.info("Container " + containerId + " no longer exists");
+    }
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/test/java/org/apache/hadoop/yarn/server/nodemanager/amrmproxy/MockResourceManagerFacade.java

@@ -486,7 +486,7 @@ public class MockResourceManagerFacade implements
   }
 
   @Override
-  public SignalContainerResponse signalContainer(
+  public SignalContainerResponse signalToContainer(
       SignalContainerRequest request) throws IOException {
 return null;
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/ClientRMService.java

@@ -1641,7 +1641,7 @@ public class ClientRMService extends AbstractService implements
    */
   @SuppressWarnings("unchecked")
   @Override
-  public SignalContainerResponse signalContainer(
+  public SignalContainerResponse signalToContainer(
       SignalContainerRequest request) throws YarnException, IOException {
     ContainerId containerId = request.getContainerId();
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/MockRM.java

@@ -1005,11 +1005,11 @@ public class MockRM extends ResourceManager {
     return activeServices;
   }
 
-  public void signalContainer(ContainerId containerId, SignalContainerCommand command)
-      throws Exception {
+  public void signalToContainer(ContainerId containerId,
+      SignalContainerCommand command) throws Exception {
     ApplicationClientProtocol client = getClientRMService();
     SignalContainerRequest req =
         SignalContainerRequest.newInstance(containerId, command);
-    client.signalContainer(req);
+    client.signalToContainer(req);
   }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/NodeManager.java

@@ -28,13 +28,14 @@ import java.util.Map;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.junit.Assert;
-
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience.Private;
 import org.apache.hadoop.yarn.api.ContainerManagementProtocol;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -317,4 +318,10 @@ public class NodeManager implements ContainerManagementProtocol {
     nodeStatus.setNodeHealthStatus(nodeHealthStatus);
     return nodeStatus;
   }
+
+  @Override
+  public synchronized SignalContainerResponse signalToContainer(
+      SignalContainerRequest request) throws YarnException, IOException {
+    throw new YarnException("Not supported yet!");
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/TestAMAuthorization.java

@@ -46,6 +46,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.RegisterApplicationMasterResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StopContainersRequest;
@@ -138,6 +140,12 @@ public class TestAMAuthorization {
       credentials.readTokenStorageStream(buf);
       return credentials;
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException, IOException {
+      return null;
+    }
   }
 
   public static class MockRMWithAMS extends MockRMWithCustomAMLauncher {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/TestApplicationMasterLauncher.java

@@ -37,6 +37,8 @@ import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceRequ
 import org.apache.hadoop.yarn.api.protocolrecords.IncreaseContainersResourceResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.GetContainerStatusesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.StartContainersResponse;
@@ -149,6 +151,12 @@ public class TestApplicationMasterLauncher {
             throws YarnException {
       return null;
     }
+
+    @Override
+    public SignalContainerResponse signalToContainer(
+        SignalContainerRequest request) throws YarnException, IOException {
+      return null;
+    }
   }
 
   @Test

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/TestSignalContainer.java

@@ -83,7 +83,7 @@ public class TestSignalContainer {
     Assert.assertEquals(request, contReceived);
 
     for(Container container : conts) {
-      rm.signalContainer(container.getId(),
+      rm.signalToContainer(container.getId(),
           SignalContainerCommand.OUTPUT_THREAD_DUMP);
     }