| /** |
| * 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 |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * 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.hadoop.mapred; |
| |
| import java.io.IOException; |
| import java.util.List; |
| |
| import org.apache.hadoop.fs.FileUtil; |
| import org.apache.hadoop.mapred.CleanupQueue.PathDeletionContext; |
| import org.apache.hadoop.mapred.JvmManager.JvmEnv; |
| import org.apache.hadoop.mapreduce.util.ProcessTree; |
| import org.apache.hadoop.util.Shell; |
| import org.apache.hadoop.util.Shell.ShellCommandExecutor; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.fs.FileUtil; |
| import org.apache.hadoop.fs.Path; |
| |
| /** |
| * The default implementation for controlling tasks. |
| * |
| * This class provides an implementation for launching and killing |
| * tasks that need to be run as the tasktracker itself. Hence, |
| * many of the initializing or cleanup methods are not required here. |
| * |
| * <br/> |
| * |
| */ |
| @InterfaceAudience.Private |
| public class DefaultTaskController extends TaskController { |
| |
| private static final Log LOG = |
| LogFactory.getLog(DefaultTaskController.class); |
| /** |
| * Launch a new JVM for the task. |
| * |
| * This method launches the new JVM for the task by executing the |
| * the JVM command using the {@link Shell.ShellCommandExecutor} |
| */ |
| void launchTaskJVM(TaskController.TaskControllerContext context) |
| throws IOException { |
| initializeTask(context); |
| |
| JvmEnv env = context.env; |
| List<String> wrappedCommand = |
| TaskLog.captureOutAndError(env.setup, env.vargs, env.stdout, env.stderr, |
| env.logSize, true); |
| ShellCommandExecutor shexec = |
| new ShellCommandExecutor(wrappedCommand.toArray(new String[0]), |
| env.workDir, env.env); |
| // set the ShellCommandExecutor for later use. |
| context.shExec = shexec; |
| shexec.execute(); |
| } |
| |
| /** |
| * Initialize the task environment. |
| * |
| * Since tasks are launched as the tasktracker user itself, this |
| * method has no action to perform. |
| */ |
| void initializeTask(TaskController.TaskControllerContext context) { |
| // The default task controller does not need to set up |
| // any permissions for proper execution. |
| // So this is a dummy method. |
| return; |
| } |
| |
| /* |
| * No need to do anything as we don't need to do as we dont need anything |
| * extra from what TaskTracker has done. |
| */ |
| @Override |
| void initializeJob(JobInitializationContext context) { |
| } |
| |
| @Override |
| void terminateTask(TaskControllerContext context) { |
| ShellCommandExecutor shexec = context.shExec; |
| if (shexec != null) { |
| Process process = shexec.getProcess(); |
| if (Shell.WINDOWS) { |
| // Currently we don't use setsid on WINDOWS. |
| //So kill the process alone. |
| if (process != null) { |
| process.destroy(); |
| } |
| } |
| else { // In addition to the task JVM, kill its subprocesses also. |
| String pid = context.pid; |
| if (pid != null) { |
| if(ProcessTree.isSetsidAvailable) { |
| ProcessTree.terminateProcessGroup(pid); |
| }else { |
| ProcessTree.terminateProcess(pid); |
| } |
| } |
| } |
| } |
| } |
| |
| @Override |
| void killTask(TaskControllerContext context) { |
| ShellCommandExecutor shexec = context.shExec; |
| if (shexec != null) { |
| if (Shell.WINDOWS) { |
| //We don't do send kill process signal in case of windows as |
| //already we have done a process.destroy() in terminateTaskJVM() |
| return; |
| } |
| String pid = context.pid; |
| if (pid != null) { |
| if(ProcessTree.isSetsidAvailable) { |
| ProcessTree.killProcessGroup(pid); |
| } else { |
| ProcessTree.killProcess(pid); |
| } |
| } |
| } |
| } |
| |
| @Override |
| void dumpTaskStack(TaskControllerContext context) { |
| ShellCommandExecutor shexec = context.shExec; |
| if (shexec != null) { |
| if (Shell.WINDOWS) { |
| // We don't use signals in Windows. |
| return; |
| } |
| String pid = context.pid; |
| if (pid != null) { |
| // Send SIGQUIT to get a stack dump |
| if (ProcessTree.isSetsidAvailable) { |
| ProcessTree.sigQuitProcessGroup(pid); |
| } else { |
| ProcessTree.sigQuitProcess(pid); |
| } |
| } |
| } |
| } |
| |
| @Override |
| public void initializeDistributedCacheFile(DistributedCacheFileContext context) |
| throws IOException { |
| Path localizedUniqueDir = context.getLocalizedUniqueDir(); |
| try { |
| // Setting recursive execute permission on localized dir |
| LOG.info("Doing chmod on localdir :" + localizedUniqueDir); |
| FileUtil.chmod(localizedUniqueDir.toString(), "+x", true); |
| } catch (InterruptedException ie) { |
| LOG.warn("Exception in doing chmod on" + localizedUniqueDir, ie); |
| throw new IOException(ie); |
| } |
| } |
| |
| @Override |
| public void initializeUser(InitializationContext context) { |
| // Do nothing. |
| } |
| |
| @Override |
| void runDebugScript(DebugScriptContext context) throws IOException { |
| List<String> wrappedCommand = TaskLog.captureDebugOut(context.args, |
| context.stdout); |
| // run the script. |
| ShellCommandExecutor shexec = |
| new ShellCommandExecutor(wrappedCommand.toArray(new String[0]), context.workDir); |
| shexec.execute(); |
| int exitCode = shexec.getExitCode(); |
| if (exitCode != 0) { |
| throw new IOException("Task debug script exit with nonzero status of " |
| + exitCode + "."); |
| } |
| } |
| |
| /** |
| * Enables the task for cleanup by changing permissions of the specified path |
| * in the local filesystem |
| */ |
| @Override |
| void enableTaskForCleanup(PathDeletionContext context) |
| throws IOException { |
| enablePathForCleanup(context); |
| } |
| |
| /** |
| * Enables the job for cleanup by changing permissions of the specified path |
| * in the local filesystem |
| */ |
| @Override |
| void enableJobForCleanup(PathDeletionContext context) |
| throws IOException { |
| enablePathForCleanup(context); |
| } |
| |
| /** |
| * Enables the path for cleanup by changing permissions of the specified path |
| * in the local filesystem |
| */ |
| private void enablePathForCleanup(PathDeletionContext context) |
| throws IOException { |
| try { |
| FileUtil.chmod(context.fullPath, "u+rwx", true); |
| } catch(InterruptedException e) { |
| LOG.warn("Interrupted while setting permissions for " + context.fullPath + |
| " for deletion."); |
| } catch(IOException ioe) { |
| LOG.warn("Unable to change permissions of " + context.fullPath); |
| } |
| } |
| } |