/**
* 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.mapreduce.server.tasktracker;
import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.mapred.TaskController;
import org.apache.hadoop.mapred.TaskLog;
import org.apache.hadoop.mapred.TaskTracker;
/**
*
* NOTE: This class is internal only and not intended for users!!
*/
public class Localizer {
static final Log LOG = LogFactory.getLog(Localizer.class);
private FileSystem fs;
private String[] localDirs;
/**
* Create a Localizer instance
*
* @param fileSys
* @param lDirs
*/
public Localizer(FileSystem fileSys, String[] lDirs) {
fs = fileSys;
localDirs = lDirs;
}
// Data-structure for synchronizing localization of user directories.
private Map<String, AtomicBoolean> localizedUsers =
new HashMap<String, AtomicBoolean>();
/**
* Initialize the local directories for a particular user on this TT. This
* involves creation and setting permissions of the following directories
* <ul>
* <li>$mapred.local.dir/taskTracker/$user</li>
* <li>$mapred.local.dir/taskTracker/$user/jobcache</li>
* <li>$mapred.local.dir/taskTracker/$user/distcache</li>
* </ul>
*
* @param user
* @throws IOException
*/
public void initializeUserDirs(String user)
throws IOException {
if (user == null) {
// This shouldn't happen in general
throw new IOException(
"User is null. Cannot initialized user-directories.");
}
AtomicBoolean localizedUser;
synchronized (localizedUsers) {
if (!localizedUsers.containsKey(user)) {
localizedUsers.put(user, new AtomicBoolean(false));
}
localizedUser = localizedUsers.get(user);
}
synchronized (localizedUser) {
if (localizedUser.get()) {
// User-directories are already localized for this user.
LOG.info("User-directories for the user " + user
+ " are already initialized on this TT. Not doing anything.");
return;
}
LOG.info("Initializing user " + user + " on this TT.");
boolean userDirStatus = false;
boolean jobCacheDirStatus = false;
boolean distributedCacheDirStatus = false;
for (String localDir : localDirs) {
Path userDir = new Path(localDir, TaskTracker.getUserDir(user));
// Set up the user-directory.
if (fs.exists(userDir) || fs.mkdirs(userDir)) {
// Set permissions on the user-directory
FsPermission userOnly = new FsPermission((short) 0700);
FileUtil.setPermission(new File(userDir.toUri().getPath()),
userOnly);
userDirStatus = true;
// Set up the jobcache directory
File jobCacheDir =
new File(localDir, TaskTracker.getJobCacheSubdir(user));
if (jobCacheDir.exists() || jobCacheDir.mkdirs()) {
// Set permissions on the jobcache-directory
FileUtil.setPermission(jobCacheDir, userOnly);
jobCacheDirStatus = true;
} else {
LOG.warn("Unable to create job cache directory : "
+ jobCacheDir);
}
// Set up the cache directory used for distributed cache files
File distributedCacheDir =
new File(localDir,
TaskTracker.getPrivateDistributedCacheDir(user));
if (distributedCacheDir.exists() || distributedCacheDir.mkdirs()) {
// Set permissions on the distcache-directory
FileUtil.setPermission(distributedCacheDir, userOnly);
distributedCacheDirStatus = true;
} else {
LOG.warn("Unable to create distributed-cache directory : "
+ distributedCacheDir);
}
} else {
LOG.warn("Unable to create the user directory : " + userDir);
}
}
if (!userDirStatus) {
throw new IOException("Not able to initialize user directories "
+ "in any of the configured local directories for user " + user);
}
if (!jobCacheDirStatus) {
throw new IOException("Not able to initialize job-cache directories "
+ "in any of the configured local directories for user " + user);
}
if (!distributedCacheDirStatus) {
throw new IOException(
"Not able to initialize distributed-cache directories "
+ "in any of the configured local directories for user "
+ user);
}
// Localization of the user is done
localizedUser.set(true);
}
}
/**
* Create taskDirs on all the disks. Otherwise, in some cases, like when
* LinuxTaskController is in use, child might wish to balance load across
* disks but cannot itself create attempt directory because of the fact that
* job directory is writable only by the TT.
*
* @param user
* @param jobId
* @param attemptId
* @throws IOException
*/
public void initializeAttemptDirs(String user, String jobId,
String attemptId)
throws IOException {
boolean initStatus = false;
String attemptDirPath =
TaskTracker.getLocalTaskDir(user, jobId, attemptId);
for (String localDir : localDirs) {
Path localAttemptDir = new Path(localDir, attemptDirPath);
boolean attemptDirStatus = fs.mkdirs(localAttemptDir);
if (!attemptDirStatus) {
LOG.warn("localAttemptDir " + localAttemptDir.toString()
+ " couldn't be created.");
}
initStatus = initStatus || attemptDirStatus;
}
if (!initStatus) {
throw new IOException("Not able to initialize attempt directories "
+ "in any of the configured local directories for the attempt "
+ attemptId);
}
}
}