/**
* 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.hdfs.server.datanode.fsdataset.impl;
import java.io.File;
import java.io.IOException;
import java.nio.channels.ClosedChannelException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import java.util.Set;
import java.util.concurrent.atomic.AtomicReference;
import com.google.common.collect.Lists;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.StorageType;
import org.apache.hadoop.hdfs.protocol.BlockListAsLongs;
import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeReference;
import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeSpi;
import org.apache.hadoop.hdfs.server.datanode.fsdataset.VolumeChoosingPolicy;
import org.apache.hadoop.hdfs.server.datanode.BlockScanner;
import org.apache.hadoop.hdfs.server.protocol.DatanodeStorage;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.util.DiskChecker.DiskErrorException;
import org.apache.hadoop.util.Time;
class FsVolumeList {
private final AtomicReference<FsVolumeImpl[]> volumes =
new AtomicReference<>(new FsVolumeImpl[0]);
// Tracks volume failures, sorted by volume path.
private final Map<String, VolumeFailureInfo> volumeFailureInfos =
Collections.synchronizedMap(new TreeMap<String, VolumeFailureInfo>());
private Object checkDirsMutex = new Object();
private final VolumeChoosingPolicy<FsVolumeImpl> blockChooser;
private final BlockScanner blockScanner;
FsVolumeList(List<VolumeFailureInfo> initialVolumeFailureInfos,
BlockScanner blockScanner,
VolumeChoosingPolicy<FsVolumeImpl> blockChooser) {
this.blockChooser = blockChooser;
this.blockScanner = blockScanner;
for (VolumeFailureInfo volumeFailureInfo: initialVolumeFailureInfos) {
volumeFailureInfos.put(volumeFailureInfo.getFailedStorageLocation(),
volumeFailureInfo);
}
}
/**
* Return an immutable list view of all the volumes.
*/
List<FsVolumeImpl> getVolumes() {
return Collections.unmodifiableList(Arrays.asList(volumes.get()));
}
private FsVolumeReference chooseVolume(List<FsVolumeImpl> list, long blockSize)
throws IOException {
while (true) {
FsVolumeImpl volume = blockChooser.chooseVolume(list, blockSize);
try {
return volume.obtainReference();
} catch (ClosedChannelException e) {
FsDatasetImpl.LOG.warn("Chosen a closed volume: " + volume);
// blockChooser.chooseVolume returns DiskOutOfSpaceException when the list
// is empty, indicating that all volumes are closed.
list.remove(volume);
}
}
}
/**
* Get next volume.
*
* @param blockSize free space needed on the volume
* @param storageType the desired {@link StorageType}
* @return next volume to store the block in.
*/
FsVolumeReference getNextVolume(StorageType storageType, long blockSize)
throws IOException {
// Get a snapshot of currently available volumes.
final FsVolumeImpl[] curVolumes = volumes.get();
final List<FsVolumeImpl> list = new ArrayList<>(curVolumes.length);
for(FsVolumeImpl v : curVolumes) {
if (v.getStorageType() == storageType) {
list.add(v);
}
}
return chooseVolume(list, blockSize);
}
/**
* Get next volume.
*
* @param blockSize free space needed on the volume
* @return next volume to store the block in.
*/
FsVolumeReference getNextTransientVolume(long blockSize) throws IOException {
// Get a snapshot of currently available volumes.
final List<FsVolumeImpl> curVolumes = getVolumes();
final List<FsVolumeImpl> list = new ArrayList<>(curVolumes.size());
for(FsVolumeImpl v : curVolumes) {
if (v.isTransientStorage()) {
list.add(v);
}
}
return chooseVolume(list, blockSize);
}
long getDfsUsed() throws IOException {
long dfsUsed = 0L;
for (FsVolumeImpl v : volumes.get()) {
try(FsVolumeReference ref = v.obtainReference()) {
dfsUsed += v.getDfsUsed();
} catch (ClosedChannelException e) {
// ignore.
}
}
return dfsUsed;
}
long getBlockPoolUsed(String bpid) throws IOException {
long dfsUsed = 0L;
for (FsVolumeImpl v : volumes.get()) {
try (FsVolumeReference ref = v.obtainReference()) {
dfsUsed += v.getBlockPoolUsed(bpid);
} catch (ClosedChannelException e) {
// ignore.
}
}
return dfsUsed;
}
long getCapacity() {
long capacity = 0L;
for (FsVolumeImpl v : volumes.get()) {
try (FsVolumeReference ref = v.obtainReference()) {
capacity += v.getCapacity();
} catch (IOException e) {
// ignore.
}
}
return capacity;
}
long getRemaining() throws IOException {
long remaining = 0L;
for (FsVolumeSpi vol : volumes.get()) {
try (FsVolumeReference ref = vol.obtainReference()) {
remaining += vol.getAvailable();
} catch (ClosedChannelException e) {
// ignore
}
}
return remaining;
}
void getAllVolumesMap(final String bpid,
final ReplicaMap volumeMap,
final RamDiskReplicaTracker ramDiskReplicaMap)
throws IOException {
long totalStartTime = Time.monotonicNow();
final List<IOException> exceptions = Collections.synchronizedList(
new ArrayList<IOException>());
List<Thread> replicaAddingThreads = new ArrayList<Thread>();
for (final FsVolumeImpl v : volumes.get()) {
Thread t = new Thread() {
public void run() {
try (FsVolumeReference ref = v.obtainReference()) {
FsDatasetImpl.LOG.info("Adding replicas to map for block pool " +
bpid + " on volume " + v + "...");
long startTime = Time.monotonicNow();
v.getVolumeMap(bpid, volumeMap, ramDiskReplicaMap);
long timeTaken = Time.monotonicNow() - startTime;
FsDatasetImpl.LOG.info("Time to add replicas to map for block pool"
+ " " + bpid + " on volume " + v + ": " + timeTaken + "ms");
} catch (ClosedChannelException e) {
FsDatasetImpl.LOG.info("The volume " + v + " is closed while " +
"addng replicas, ignored.");
} catch (IOException ioe) {
FsDatasetImpl.LOG.info("Caught exception while adding replicas " +
"from " + v + ". Will throw later.", ioe);
exceptions.add(ioe);
}
}
};
replicaAddingThreads.add(t);
t.start();
}
for (Thread t : replicaAddingThreads) {
try {
t.join();
} catch (InterruptedException ie) {
throw new IOException(ie);
}
}
if (!exceptions.isEmpty()) {
throw exceptions.get(0);
}
long totalTimeTaken = Time.monotonicNow() - totalStartTime;
FsDatasetImpl.LOG.info("Total time to add all replicas to map: "
+ totalTimeTaken + "ms");
}
/**
* Calls {@link FsVolumeImpl#checkDirs()} on each volume.
*
* Use checkDirsMutext to allow only one instance of checkDirs() call
*
* @return list of all the failed volumes.
*/
Set<File> checkDirs() {
synchronized(checkDirsMutex) {
Set<File> failedVols = null;
// Make a copy of volumes for performing modification
final List<FsVolumeImpl> volumeList = getVolumes();
for(Iterator<FsVolumeImpl> i = volumeList.iterator(); i.hasNext(); ) {
final FsVolumeImpl fsv = i.next();
try (FsVolumeReference ref = fsv.obtainReference()) {
fsv.checkDirs();
} catch (DiskErrorException e) {
FsDatasetImpl.LOG.warn("Removing failed volume " + fsv + ": ", e);
if (failedVols == null) {
failedVols = new HashSet<>(1);
}
failedVols.add(new File(fsv.getBasePath()).getAbsoluteFile());
addVolumeFailureInfo(fsv);
removeVolume(fsv);
} catch (ClosedChannelException e) {
FsDatasetImpl.LOG.debug("Caught exception when obtaining " +
"reference count on closed volume", e);
} catch (IOException e) {
FsDatasetImpl.LOG.error("Unexpected IOException", e);
}
}
if (failedVols != null && failedVols.size() > 0) {
FsDatasetImpl.LOG.warn("Completed checkDirs. Found " + failedVols.size()
+ " failure volumes.");
}
return failedVols;
}
}
@Override
public String toString() {
return Arrays.toString(volumes.get());
}
/**
* Dynamically add new volumes to the existing volumes that this DN manages.
*
* @param ref a reference to the new FsVolumeImpl instance.
*/
void addVolume(FsVolumeReference ref) {
FsVolumeImpl volume = (FsVolumeImpl) ref.getVolume();
while (true) {
final FsVolumeImpl[] curVolumes = volumes.get();
final List<FsVolumeImpl> volumeList = Lists.newArrayList(curVolumes);
volumeList.add(volume);
if (volumes.compareAndSet(curVolumes,
volumeList.toArray(new FsVolumeImpl[volumeList.size()]))) {
break;
} else {
if (FsDatasetImpl.LOG.isDebugEnabled()) {
FsDatasetImpl.LOG.debug(
"The volume list has been changed concurrently, " +
"retry to remove volume: " + ref.getVolume().getStorageID());
}
}
}
if (blockScanner != null) {
blockScanner.addVolumeScanner(ref);
} else {
// If the volume is not put into a volume scanner, it does not need to
// hold the reference.
IOUtils.cleanup(FsDatasetImpl.LOG, ref);
}
// If the volume is used to replace a failed volume, it needs to reset the
// volume failure info for this volume.
removeVolumeFailureInfo(new File(volume.getBasePath()));
FsDatasetImpl.LOG.info("Added new volume: " +
volume.getStorageID());
}
/**
* Dynamically remove a volume in the list.
* @param target the volume instance to be removed.
*/
private void removeVolume(FsVolumeImpl target) {
while (true) {
final FsVolumeImpl[] curVolumes = volumes.get();
final List<FsVolumeImpl> volumeList = Lists.newArrayList(curVolumes);
if (volumeList.remove(target)) {
if (volumes.compareAndSet(curVolumes,
volumeList.toArray(new FsVolumeImpl[volumeList.size()]))) {
if (blockScanner != null) {
blockScanner.removeVolumeScanner(target);
}
try {
target.closeAndWait();
} catch (IOException e) {
FsDatasetImpl.LOG.warn(
"Error occurs when waiting volume to close: " + target, e);
}
target.shutdown();
FsDatasetImpl.LOG.info("Removed volume: " + target);
break;
} else {
if (FsDatasetImpl.LOG.isDebugEnabled()) {
FsDatasetImpl.LOG.debug(
"The volume list has been changed concurrently, " +
"retry to remove volume: " + target);
}
}
} else {
if (FsDatasetImpl.LOG.isDebugEnabled()) {
FsDatasetImpl.LOG.debug("Volume " + target +
" does not exist or is removed by others.");
}
break;
}
}
}
/**
* Dynamically remove volume in the list.
* @param volume the volume to be removed.
* @param clearFailure set true to remove failure info for this volume.
*/
void removeVolume(File volume, boolean clearFailure) {
// Make a copy of volumes to remove one volume.
final FsVolumeImpl[] curVolumes = volumes.get();
final List<FsVolumeImpl> volumeList = Lists.newArrayList(curVolumes);
for (Iterator<FsVolumeImpl> it = volumeList.iterator(); it.hasNext(); ) {
FsVolumeImpl fsVolume = it.next();
String basePath, targetPath;
basePath = new File(fsVolume.getBasePath()).getAbsolutePath();
targetPath = volume.getAbsolutePath();
if (basePath.equals(targetPath)) {
// Make sure the removed volume is the one in the curVolumes.
removeVolume(fsVolume);
}
}
if (clearFailure) {
removeVolumeFailureInfo(volume);
}
}
VolumeFailureInfo[] getVolumeFailureInfos() {
Collection<VolumeFailureInfo> infos = volumeFailureInfos.values();
return infos.toArray(new VolumeFailureInfo[infos.size()]);
}
void addVolumeFailureInfo(VolumeFailureInfo volumeFailureInfo) {
volumeFailureInfos.put(volumeFailureInfo.getFailedStorageLocation(),
volumeFailureInfo);
}
private void addVolumeFailureInfo(FsVolumeImpl vol) {
addVolumeFailureInfo(new VolumeFailureInfo(
new File(vol.getBasePath()).getAbsolutePath(),
Time.now(),
vol.getCapacity()));
}
private void removeVolumeFailureInfo(File vol) {
volumeFailureInfos.remove(vol.getAbsolutePath());
}
void addBlockPool(final String bpid, final Configuration conf) throws IOException {
long totalStartTime = Time.monotonicNow();
final List<IOException> exceptions = Collections.synchronizedList(
new ArrayList<IOException>());
List<Thread> blockPoolAddingThreads = new ArrayList<Thread>();
for (final FsVolumeImpl v : volumes.get()) {
Thread t = new Thread() {
public void run() {
try (FsVolumeReference ref = v.obtainReference()) {
FsDatasetImpl.LOG.info("Scanning block pool " + bpid +
" on volume " + v + "...");
long startTime = Time.monotonicNow();
v.addBlockPool(bpid, conf);
long timeTaken = Time.monotonicNow() - startTime;
FsDatasetImpl.LOG.info("Time taken to scan block pool " + bpid +
" on " + v + ": " + timeTaken + "ms");
} catch (ClosedChannelException e) {
// ignore.
} catch (IOException ioe) {
FsDatasetImpl.LOG.info("Caught exception while scanning " + v +
". Will throw later.", ioe);
exceptions.add(ioe);
}
}
};
blockPoolAddingThreads.add(t);
t.start();
}
for (Thread t : blockPoolAddingThreads) {
try {
t.join();
} catch (InterruptedException ie) {
throw new IOException(ie);
}
}
if (!exceptions.isEmpty()) {
throw exceptions.get(0);
}
long totalTimeTaken = Time.monotonicNow() - totalStartTime;
FsDatasetImpl.LOG.info("Total time to scan all replicas for block pool " +
bpid + ": " + totalTimeTaken + "ms");
}
void removeBlockPool(String bpid, Map<DatanodeStorage, BlockListAsLongs>
blocksPerVolume) {
for (FsVolumeImpl v : volumes.get()) {
v.shutdownBlockPool(bpid, blocksPerVolume.get(v.toDatanodeStorage()));
}
}
void shutdown() {
for (FsVolumeImpl volume : volumes.get()) {
if(volume != null) {
volume.shutdown();
}
}
}
}