org.apache.flink.runtime.io.network.netty.PartitionRequestClientFactory Maven / Gradle / Ivy
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* distributed with this work for additional information
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* 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.flink.runtime.io.network.netty;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import org.apache.flink.runtime.io.network.ConnectionID;
import org.apache.flink.runtime.io.network.netty.exception.LocalTransportException;
import org.apache.flink.runtime.io.network.netty.exception.RemoteTransportException;
import org.apache.flink.runtime.io.network.partition.consumer.RemoteInputChannel;
import java.io.IOException;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
* Factory for {@link PartitionRequestClient} instances.
*
* Instances of partition requests clients are shared among several {@link RemoteInputChannel}
* instances.
*/
class PartitionRequestClientFactory {
private final NettyClient nettyClient;
private final ConcurrentMap clients = new ConcurrentHashMap();
PartitionRequestClientFactory(NettyClient nettyClient) {
this.nettyClient = nettyClient;
}
/**
* Atomically establishes a TCP connection to the given remote address and
* creates a {@link PartitionRequestClient} instance for this connection.
*/
PartitionRequestClient createPartitionRequestClient(ConnectionID connectionId) throws IOException, InterruptedException {
Object entry;
PartitionRequestClient client = null;
while (client == null) {
entry = clients.get(connectionId);
if (entry != null) {
// Existing channel or connecting channel
if (entry instanceof PartitionRequestClient) {
client = (PartitionRequestClient) entry;
}
else {
ConnectingChannel future = (ConnectingChannel) entry;
client = future.waitForChannel();
clients.replace(connectionId, future, client);
}
}
else {
// No channel yet. Create one, but watch out for a race.
// We create a "connecting future" and atomically add it to the map.
// Only the thread that really added it establishes the channel.
// The others need to wait on that original establisher's future.
ConnectingChannel connectingChannel = new ConnectingChannel(connectionId, this);
Object old = clients.putIfAbsent(connectionId, connectingChannel);
if (old == null) {
nettyClient.connect(connectionId.getAddress()).addListener(connectingChannel);
client = connectingChannel.waitForChannel();
clients.replace(connectionId, connectingChannel, client);
}
else if (old instanceof ConnectingChannel) {
client = ((ConnectingChannel) old).waitForChannel();
clients.replace(connectionId, old, client);
}
else {
client = (PartitionRequestClient) old;
}
}
// Make sure to increment the reference count before handing a client
// out to ensure correct bookkeeping for channel closing.
if (!client.incrementReferenceCounter()) {
destroyPartitionRequestClient(connectionId, client);
client = null;
}
}
return client;
}
public void closeOpenChannelConnections(ConnectionID connectionId) {
Object entry = clients.get(connectionId);
if (entry instanceof ConnectingChannel) {
ConnectingChannel channel = (ConnectingChannel) entry;
if (channel.dispose()) {
clients.remove(connectionId, channel);
}
}
}
int getNumberOfActiveClients() {
return clients.size();
}
/**
* Removes the client for the given {@link ConnectionID}.
*/
void destroyPartitionRequestClient(ConnectionID connectionId, PartitionRequestClient client) {
clients.remove(connectionId, client);
}
private static final class ConnectingChannel implements ChannelFutureListener {
private final Object connectLock = new Object();
private final ConnectionID connectionId;
private final PartitionRequestClientFactory clientFactory;
private boolean disposeRequestClient = false;
public ConnectingChannel(ConnectionID connectionId, PartitionRequestClientFactory clientFactory) {
this.connectionId = connectionId;
this.clientFactory = clientFactory;
}
private boolean dispose() {
boolean result;
synchronized (connectLock) {
if (partitionRequestClient != null) {
result = partitionRequestClient.disposeIfNotUsed();
}
else {
disposeRequestClient = true;
result = true;
}
connectLock.notifyAll();
}
return result;
}
private void handInChannel(Channel channel) {
synchronized (connectLock) {
try {
PartitionRequestClientHandler requestHandler = channel.pipeline()
.get(PartitionRequestClientHandler.class);
partitionRequestClient = new PartitionRequestClient(
channel, requestHandler, connectionId, clientFactory);
if (disposeRequestClient) {
partitionRequestClient.disposeIfNotUsed();
}
connectLock.notifyAll();
}
catch (Throwable t) {
notifyOfError(t);
}
}
}
private volatile PartitionRequestClient partitionRequestClient;
private volatile Throwable error;
private PartitionRequestClient waitForChannel() throws IOException, InterruptedException {
synchronized (connectLock) {
while (error == null && partitionRequestClient == null) {
connectLock.wait(2000);
}
}
if (error != null) {
throw new IOException("Connecting the channel failed: " + error.getMessage(), error);
}
return partitionRequestClient;
}
private void notifyOfError(Throwable error) {
synchronized (connectLock) {
this.error = error;
connectLock.notifyAll();
}
}
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
handInChannel(future.channel());
}
else if (future.cause() != null) {
notifyOfError(new RemoteTransportException(
"Connecting to remote task manager + '" + connectionId.getAddress() +
"' has failed. This might indicate that the remote task " +
"manager has been lost.",
connectionId.getAddress(), future.cause()));
}
else {
notifyOfError(new LocalTransportException(
"Connecting to remote task manager + '" + connectionId.getAddress() +
"' has been cancelled.", null));
}
}
}
}