/**
* Copyright 2010 The Apache Software Foundation
*
* 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.hbase.master;
import java.io.IOException;
import java.util.Map;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HServerInfo;
import org.apache.hadoop.hbase.RemoteExceptionHandler;
import org.apache.hadoop.hbase.Server;
import org.apache.hadoop.hbase.master.metrics.MasterMetrics;
import org.apache.hadoop.hbase.regionserver.HRegion;
import org.apache.hadoop.hbase.regionserver.Store;
import org.apache.hadoop.hbase.regionserver.wal.HLog;
import org.apache.hadoop.hbase.regionserver.wal.HLogSplitter;
import org.apache.hadoop.hbase.regionserver.wal.OrphanHLogAfterSplitException;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.FSUtils;
/**
* This class abstracts a bunch of operations the HMaster needs to interact with
* the underlying file system, including splitting log files, checking file
* system status, etc.
*/
public class MasterFileSystem {
private static final Log LOG = LogFactory.getLog(MasterFileSystem.class.getName());
// HBase configuration
Configuration conf;
// master status
Server master;
// metrics for master
MasterMetrics metrics;
// Keep around for convenience.
private final FileSystem fs;
// Is the fileystem ok?
private volatile boolean fsOk = true;
// The Path to the old logs dir
private final Path oldLogDir;
// root hbase directory on the FS
private final Path rootdir;
// create the split log lock
final Lock splitLogLock = new ReentrantLock();
public MasterFileSystem(Server master, MasterMetrics metrics)
throws IOException {
this.conf = master.getConfiguration();
this.master = master;
this.metrics = metrics;
// Set filesystem to be that of this.rootdir else we get complaints about
// mismatched filesystems if hbase.rootdir is hdfs and fs.defaultFS is
// default localfs. Presumption is that rootdir is fully-qualified before
// we get to here with appropriate fs scheme.
this.rootdir = FSUtils.getRootDir(conf);
// Cover both bases, the old way of setting default fs and the new.
// We're supposed to run on 0.20 and 0.21 anyways.
conf.set("fs.default.name", this.rootdir.toString());
conf.set("fs.defaultFS", this.rootdir.toString());
// setup the filesystem variable
this.fs = FileSystem.get(conf);
// set up the archived logs path
this.oldLogDir = new Path(this.rootdir, HConstants.HREGION_OLDLOGDIR_NAME);
createInitialFileSystemLayout();
}
/**
* Create initial layout in filesystem.
* <ol>
* <li>Check if the root region exists and is readable, if not create it.
* Create hbase.version and the -ROOT- directory if not one.
* </li>
* <li>Create a log archive directory for RS to put archived logs</li>
* </ol>
* Idempotent.
*/
private void createInitialFileSystemLayout() throws IOException {
// check if the root directory exists
checkRootDir(this.rootdir, conf, this.fs);
// Make sure the region servers can archive their old logs
if(!this.fs.exists(this.oldLogDir)) {
this.fs.mkdirs(this.oldLogDir);
}
}
public FileSystem getFileSystem() {
return this.fs;
}
/**
* Get the directory where old logs go
* @return the dir
*/
public Path getOldLogDir() {
return this.oldLogDir;
}
/**
* Checks to see if the file system is still accessible.
* If not, sets closed
* @return false if file system is not available
*/
public boolean checkFileSystem() {
if (this.fsOk) {
try {
FSUtils.checkFileSystemAvailable(this.fs);
} catch (IOException e) {
master.abort("Shutting down HBase cluster: file system not available", e);
this.fsOk = false;
}
}
return this.fsOk;
}
/**
* @return HBase root dir.
* @throws IOException
*/
public Path getRootDir() {
return this.rootdir;
}
/**
* Inspect the log directory to recover any log file without
* an active region server.
* @param onlineServers Map of online servers keyed by
* {@link HServerInfo#getServerName()}
*/
void splitLogAfterStartup(final Map<String, HServerInfo> onlineServers) {
Path logsDirPath = new Path(this.rootdir, HConstants.HREGION_LOGDIR_NAME);
try {
if (!this.fs.exists(logsDirPath)) {
return;
}
} catch (IOException e) {
throw new RuntimeException("Failed exists test on " + logsDirPath, e);
}
FileStatus[] logFolders;
try {
logFolders = this.fs.listStatus(logsDirPath);
} catch (IOException e) {
throw new RuntimeException("Failed listing " + logsDirPath.toString(), e);
}
if (logFolders == null || logFolders.length == 0) {
LOG.debug("No log files to split, proceeding...");
return;
}
for (FileStatus status : logFolders) {
String serverName = status.getPath().getName();
if (onlineServers.get(serverName) == null) {
LOG.info("Log folder " + status.getPath() + " doesn't belong " +
"to a known region server, splitting");
splitLog(serverName);
} else {
LOG.info("Log folder " + status.getPath() +
" belongs to an existing region server");
}
}
}
public void splitLog(final String serverName) {
this.splitLogLock.lock();
long splitTime = 0, splitLogSize = 0;
Path logDir = new Path(this.rootdir, HLog.getHLogDirectoryName(serverName));
try {
HLogSplitter splitter = HLogSplitter.createLogSplitter(conf);
try {
splitter.splitLog(this.rootdir, logDir, oldLogDir, this.fs, conf);
} catch (OrphanHLogAfterSplitException e) {
LOG.warn("Retrying splitting because of:", e);
splitter.splitLog(this.rootdir, logDir, oldLogDir, this.fs, conf);
}
splitTime = splitter.getTime();
splitLogSize = splitter.getSize();
} catch (IOException e) {
LOG.error("Failed splitting " + logDir.toString(), e);
} finally {
this.splitLogLock.unlock();
}
if (this.metrics != null) {
this.metrics.addSplit(splitTime, splitLogSize);
}
}
/**
* Get the rootdir. Make sure its wholesome and exists before returning.
* @param rd
* @param conf
* @param fs
* @return hbase.rootdir (after checks for existence and bootstrapping if
* needed populating the directory with necessary bootup files).
* @throws IOException
*/
private static Path checkRootDir(final Path rd, final Configuration c,
final FileSystem fs)
throws IOException {
// If FS is in safe mode wait till out of it.
FSUtils.waitOnSafeMode(c, c.getInt(HConstants.THREAD_WAKE_FREQUENCY,
10 * 1000));
// Filesystem is good. Go ahead and check for hbase.rootdir.
if (!fs.exists(rd)) {
fs.mkdirs(rd);
FSUtils.setVersion(fs, rd);
} else {
FSUtils.checkVersion(fs, rd, true);
}
// Make sure the root region directory exists!
if (!FSUtils.rootRegionExists(fs, rd)) {
bootstrap(rd, c);
}
return rd;
}
private static void bootstrap(final Path rd, final Configuration c)
throws IOException {
LOG.info("BOOTSTRAP: creating ROOT and first META regions");
try {
// Bootstrapping, make sure blockcache is off. Else, one will be
// created here in bootstap and it'll need to be cleaned up. Better to
// not make it in first place. Turn off block caching for bootstrap.
// Enable after.
HRegionInfo rootHRI = new HRegionInfo(HRegionInfo.ROOT_REGIONINFO);
setInfoFamilyCaching(rootHRI, false);
HRegionInfo metaHRI = new HRegionInfo(HRegionInfo.FIRST_META_REGIONINFO);
setInfoFamilyCaching(metaHRI, false);
HRegion root = HRegion.createHRegion(rootHRI, rd, c);
HRegion meta = HRegion.createHRegion(metaHRI, rd, c);
setInfoFamilyCaching(rootHRI, true);
setInfoFamilyCaching(metaHRI, true);
// Add first region from the META table to the ROOT region.
HRegion.addRegionToMETA(root, meta);
root.close();
root.getLog().closeAndDelete();
meta.close();
meta.getLog().closeAndDelete();
} catch (IOException e) {
e = RemoteExceptionHandler.checkIOException(e);
LOG.error("bootstrap", e);
throw e;
}
}
/**
* @param hri Set all family block caching to <code>b</code>
* @param b
*/
private static void setInfoFamilyCaching(final HRegionInfo hri, final boolean b) {
for (HColumnDescriptor hcd: hri.getTableDesc().families.values()) {
if (Bytes.equals(hcd.getName(), HConstants.CATALOG_FAMILY)) {
hcd.setBlockCacheEnabled(b);
hcd.setInMemory(b);
}
}
}
public void deleteRegion(HRegionInfo region) throws IOException {
fs.delete(HRegion.getRegionDir(rootdir, region), true);
}
public void deleteTable(byte[] tableName) throws IOException {
fs.delete(new Path(rootdir, Bytes.toString(tableName)), true);
}
public void updateRegionInfo(HRegionInfo region) {
// TODO implement this. i think this is currently broken in trunk i don't
// see this getting updated.
// @see HRegion.checkRegioninfoOnFilesystem()
}
public void deleteFamily(HRegionInfo region, byte[] familyName)
throws IOException {
fs.delete(Store.getStoreHomedir(
new Path(rootdir, region.getTableDesc().getNameAsString()),
region.getEncodedName(), familyName), true);
}
}