org.apache.cassandra.service.AbstractWriteResponseHandler Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of cassandra-all Show documentation
Show all versions of cassandra-all Show documentation
The Apache Cassandra Project develops a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model.
/*
* 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.cassandra.service;
import java.net.InetAddress;
import java.util.Collection;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import com.google.common.collect.Iterables;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.db.ConsistencyLevel;
import org.apache.cassandra.db.Keyspace;
import org.apache.cassandra.db.WriteType;
import org.apache.cassandra.exceptions.*;
import org.apache.cassandra.net.IAsyncCallbackWithFailure;
import org.apache.cassandra.net.MessageIn;
import org.apache.cassandra.utils.concurrent.SimpleCondition;
public abstract class AbstractWriteResponseHandler implements IAsyncCallbackWithFailure
{
protected static final Logger logger = LoggerFactory.getLogger( AbstractWriteResponseHandler.class );
private final SimpleCondition condition = new SimpleCondition();
protected final Keyspace keyspace;
protected final Collection naturalEndpoints;
public final ConsistencyLevel consistencyLevel;
protected final Runnable callback;
protected final Collection pendingEndpoints;
protected final WriteType writeType;
private static final AtomicIntegerFieldUpdater failuresUpdater
= AtomicIntegerFieldUpdater.newUpdater(AbstractWriteResponseHandler.class, "failures");
private volatile int failures = 0;
private final Map failureReasonByEndpoint;
private final long queryStartNanoTime;
private volatile boolean supportsBackPressure = true;
/**
* @param callback A callback to be called when the write is successful.
* @param queryStartNanoTime
*/
protected AbstractWriteResponseHandler(Keyspace keyspace,
Collection naturalEndpoints,
Collection pendingEndpoints,
ConsistencyLevel consistencyLevel,
Runnable callback,
WriteType writeType,
long queryStartNanoTime)
{
this.keyspace = keyspace;
this.pendingEndpoints = pendingEndpoints;
this.consistencyLevel = consistencyLevel;
this.naturalEndpoints = naturalEndpoints;
this.callback = callback;
this.writeType = writeType;
this.failureReasonByEndpoint = new ConcurrentHashMap<>();
this.queryStartNanoTime = queryStartNanoTime;
}
public void get() throws WriteTimeoutException, WriteFailureException
{
long timeout = currentTimeout();
boolean success;
try
{
success = condition.await(timeout, TimeUnit.NANOSECONDS);
}
catch (InterruptedException ex)
{
throw new AssertionError(ex);
}
if (!success)
{
int blockedFor = totalBlockFor();
int acks = ackCount();
// It's pretty unlikely, but we can race between exiting await above and here, so
// that we could now have enough acks. In that case, we "lie" on the acks count to
// avoid sending confusing info to the user (see CASSANDRA-6491).
if (acks >= blockedFor)
acks = blockedFor - 1;
throw new WriteTimeoutException(writeType, consistencyLevel, acks, blockedFor);
}
if (totalBlockFor() + failures > totalEndpoints())
{
throw new WriteFailureException(consistencyLevel, ackCount(), totalBlockFor(), writeType, failureReasonByEndpoint);
}
}
public final long currentTimeout()
{
long requestTimeout = writeType == WriteType.COUNTER
? DatabaseDescriptor.getCounterWriteRpcTimeout()
: DatabaseDescriptor.getWriteRpcTimeout();
return TimeUnit.MILLISECONDS.toNanos(requestTimeout) - (System.nanoTime() - queryStartNanoTime);
}
/**
* @return the minimum number of endpoints that must reply.
*/
protected int totalBlockFor()
{
// During bootstrap, we have to include the pending endpoints or we may fail the consistency level
// guarantees (see #833)
return consistencyLevel.blockFor(keyspace) + pendingEndpoints.size();
}
/**
* @return the total number of endpoints the request has been sent to.
*/
protected int totalEndpoints()
{
if (consistencyLevel != null && consistencyLevel.isDatacenterLocal())
return consistencyLevel.countLocalEndpoints(Iterables.concat(naturalEndpoints, pendingEndpoints));
return naturalEndpoints.size() + pendingEndpoints.size();
}
/**
* @return true if the message counts towards the totalBlockFor() threshold
*/
protected boolean waitingFor(InetAddress from)
{
return true;
}
/**
* @return number of responses received
*/
protected abstract int ackCount();
/** null message means "response from local write" */
public abstract void response(MessageIn msg);
public void assureSufficientLiveNodes() throws UnavailableException
{
consistencyLevel.assureSufficientLiveNodes(keyspace, Iterables.filter(Iterables.concat(naturalEndpoints, pendingEndpoints), isAlive));
}
protected void signal()
{
condition.signalAll();
if (callback != null)
callback.run();
}
@Override
public void onFailure(InetAddress from, RequestFailureReason failureReason)
{
logger.trace("Got failure from {}", from);
int n = waitingFor(from)
? failuresUpdater.incrementAndGet(this)
: failures;
failureReasonByEndpoint.put(from, failureReason);
if (totalBlockFor() + n > totalEndpoints())
signal();
}
@Override
public boolean supportsBackPressure()
{
return supportsBackPressure;
}
public void setSupportsBackPressure(boolean supportsBackPressure)
{
this.supportsBackPressure = supportsBackPressure;
}
}