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WIP - pre-lib for jctools

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nathan 2015-05-06 20:47:02 +02:00
parent f96a2f4c19
commit 1a591165a8
21 changed files with 1214 additions and 1933 deletions
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104
src/main/java/com/lmax/disruptor/DisruptorQueue.java
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@ -1,104 +0,0 @@
package com.lmax.disruptor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedTransferQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import dorkbox.util.messagebus.MultiMBassador;
import dorkbox.util.messagebus.common.NamedThreadFactory;
public class DisruptorQueue {
private static final int AVAILABLE_PROCESSORS = Runtime.getRuntime().availableProcessors();
private final ExecutorService executor;
// must be power of 2.
private final int ringBufferSize = 1;
private final RingBuffer<MessageHolder> ringBuffer;
private WaitingWorkerPool<MessageHolder> workerPool;
public DisruptorQueue(MultiMBassador mbassador, int numberOfThreads) {
// numberOfThreads = 4;
// only used to startup threads, can be replaced with static list of threads
this.executor = new ThreadPoolExecutor(numberOfThreads, numberOfThreads, 0,
TimeUnit.NANOSECONDS,
new LinkedTransferQueue<Runnable>(),
new NamedThreadFactory("disruptor"));
EventBusFactory factory = new EventBusFactory();
PublicationExceptionHandler loggingExceptionHandler = new PublicationExceptionHandler(mbassador);
WorkHandlerEarlyRelease<MessageHolder> handlers[] = new EventProcessor2[numberOfThreads];
for (int i = 0; i < handlers.length; i++) {
handlers[i] = new EventProcessor2(mbassador);
}
WaitStrategy consumerWaitStrategy = new BlockingWaitStrategy();
WaitingMultiProducerSequencer sequencer = new WaitingMultiProducerSequencer(4, loggingExceptionHandler, consumerWaitStrategy);
this.ringBuffer = new RingBuffer<MessageHolder>(factory, sequencer);
SequenceBarrier sequenceBarrier = this.ringBuffer.newBarrier();
this.workerPool = new WaitingWorkerPool<MessageHolder>(this.ringBuffer,
sequencer,
sequenceBarrier,
loggingExceptionHandler,
handlers);
sequencer.addGatingSequences(this.workerPool.getWorkerSequences()); // to notify our consumers (if they are blocking) of a new element
this.workerPool.start(this.executor);
}
public void transfer(Object message1) throws InterruptedException {
// put this on the disruptor ring buffer
final RingBuffer<MessageHolder> ringBuffer = this.ringBuffer;
// setup the job
final long seq = ringBuffer.next();
try {
// System.err.println("+(" + seq + ") " + message1);
MessageHolder eventJob = ringBuffer.get(seq);
eventJob.messageType = MessageTypeOLD.ONE;
eventJob.message1 = message1;
// eventJob.message2 = message2;
// eventJob.message3 = message3;
} catch (Exception e) {
e.printStackTrace();
// handlePublicationError(new PublicationError()
// .setMessage("Error while adding an asynchronous message")
// .setCause(e)
// .setPublishedObject(message1));
} finally {
// always publish the job
ringBuffer.publish(seq);
}
}
public boolean hasPendingMessages() {
final long cursor = this.ringBuffer.getCursor();
Sequence[] workerSequences = this.workerPool.getWorkerSequences();
for (Sequence s : workerSequences) {
if (cursor > s.get())
{
return true;
}
}
return false;
}
public void tryTransfer(Runnable runnable, long timeout, TimeUnit unit) throws InterruptedException {
// TODO Auto-generated method stub
}
}

18
src/main/java/com/lmax/disruptor/EventBusFactory.java
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package com.lmax.disruptor;
import com.lmax.disruptor.EventFactory;
/**
* @author dorkbox, llc
* Date: 2/2/15
*/
public class EventBusFactory implements EventFactory<MessageHolder> {
public EventBusFactory() {
}
@Override
public MessageHolder newInstance() {
return new MessageHolder();
}
}

53
src/main/java/com/lmax/disruptor/EventProcessor2.java
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@ -1,53 +0,0 @@
package com.lmax.disruptor;
import dorkbox.util.messagebus.PubSubSupport;
/**
* @author dorkbox, llc
* Date: 2/2/15
*/
public class EventProcessor2 implements WorkHandlerEarlyRelease<MessageHolder> {
private final PubSubSupport publisher;
private WaitingWorkProcessor workProcessor;
public EventProcessor2(PubSubSupport publisher) {
this.publisher = publisher;
}
@Override
public void setProcessor(WaitingWorkProcessor workProcessor) {
// this.workProcessor = workProcessor;
}
@Override
public void onEvent(long sequence, MessageHolder event) throws Exception {
MessageTypeOLD messageType = event.messageType;
switch (messageType) {
case ONE: {
Object message1 = event.message1;
// System.err.println("(" + sequence + ")" + message1);
// this.workProcessor.release(sequence);
this.publisher.publish(message1);
return;
}
case TWO: {
Object message1 = event.message1;
Object message2 = event.message2;
this.publisher.publish(message1, message2);
return;
}
case THREE: {
Object message1 = event.message1;
Object message2 = event.message2;
Object message3 = event.message3;
this.publisher.publish(message1, message2, message3);
return;
}
case ARRAY: {
Object[] messages = event.messages;
this.publisher.publish(messages);
return;
}
}
}
}

16
src/main/java/com/lmax/disruptor/MessageHolder.java
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package com.lmax.disruptor;
/**
* @author dorkbox, llc Date: 2/2/15
*/
public class MessageHolder {
public MessageTypeOLD messageType = MessageTypeOLD.ONE;
public Object message1 = null;
public Object message2 = null;
public Object message3 = null;
public Object[] messages = null;
public MessageHolder() {}
}

8
src/main/java/com/lmax/disruptor/MessageTypeOLD.java
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package com.lmax.disruptor;
/**
* @author dorkbox, llc
* Date: 2/2/15
*/
public enum MessageTypeOLD {
ONE, TWO, THREE, ARRAY
}

35
src/main/java/com/lmax/disruptor/PublicationExceptionHandler.java
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package com.lmax.disruptor;
import com.lmax.disruptor.ExceptionHandler;
import dorkbox.util.messagebus.error.ErrorHandlingSupport;
import dorkbox.util.messagebus.error.PublicationError;
public final class PublicationExceptionHandler implements ExceptionHandler {
private final ErrorHandlingSupport errorHandler;
public PublicationExceptionHandler(ErrorHandlingSupport errorHandler) {
this.errorHandler = errorHandler;
}
@Override
public void handleEventException(final Throwable e, final long sequence, final Object event) {
this.errorHandler.handlePublicationError(new PublicationError()
.setMessage("Exception processing: " + sequence + " " + event.getClass() + "(" + event + ")")
.setCause(e));
}
@Override
public void handleOnStartException(final Throwable e) {
this.errorHandler.handlePublicationError(new PublicationError()
.setMessage("Error starting the disruptor")
.setCause(e));
}
@Override
public void handleOnShutdownException(final Throwable e) {
this.errorHandler.handlePublicationError(new PublicationError()
.setMessage("Error stopping the disruptor")
.setCause(e));
}
}

371
src/main/java/com/lmax/disruptor/WaitingMultiProducerSequencer.java
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/*
* Copyright 2011 LMAX Ltd.
*
* Licensed 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 com.lmax.disruptor;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.LockSupport;
import java.util.concurrent.locks.ReentrantLock;
import sun.misc.Unsafe;
import com.lmax.disruptor.util.Util;
/**
* <p>Coordinator for claiming sequences for access to a data structure while tracking dependent {@link Sequence}s.
* Suitable for use for sequencing across multiple publisher threads.</p>
*
* <p> * <p>Note on {@link Sequencer#getCursor()}: With this sequencer the cursor value is updated after the call
* to {@link Sequencer#next()}, to determine the highest available sequence that can be read, then
* {@link Sequencer#getHighestPublishedSequence(long, long)} should be used.
*/
public final class WaitingMultiProducerSequencer extends AbstractSequencer implements WaitStrategy
{
private static final Unsafe UNSAFE = Util.getUnsafe();
private static final long BASE = UNSAFE.arrayBaseOffset(int[].class);
private static final long SCALE = UNSAFE.arrayIndexScale(int[].class);
private final Sequence gatingSequenceCache = new Sequence(Sequencer.INITIAL_CURSOR_VALUE);
private final Lock lock = new ReentrantLock();
private final Condition processorNotifyCondition = this.lock.newCondition();
private final AtomicBoolean running = new AtomicBoolean(true);
private final ExceptionHandler exceptionHandler;
// availableBuffer tracks the state of each ringbuffer slot
// see below for more details on the approach
private final int[] availableBuffer;
private final int indexMask;
private final int indexShift;
/**
* Construct a Sequencer with the selected wait strategy and buffer size.
*
* @param bufferSize the size of the buffer that this will sequence over.
* @param producerWaitStrategy for those producing sequences
* @param consumerWaitStrategy for those waiting on sequences.
*/
public WaitingMultiProducerSequencer(int bufferSize, ExceptionHandler exceptionHandler, WaitStrategy consumerWaitStrategy)
{
super(bufferSize, consumerWaitStrategy);
this.exceptionHandler = exceptionHandler;
this.availableBuffer = new int[bufferSize];
this.indexMask = bufferSize - 1;
this.indexShift = Util.log2(bufferSize);
initialiseAvailableBuffer();
}
public void halt() {
this.running.set(false);
signalAllWhenBlocking();
}
/**
* @see Sequencer#hasAvailableCapacity(int)
*/
@Override
public boolean hasAvailableCapacity(final int requiredCapacity)
{
return hasAvailableCapacity(this.gatingSequences, requiredCapacity, this.cursor.get());
}
private boolean hasAvailableCapacity(Sequence[] gatingSequences, final int requiredCapacity, long cursorValue)
{
long wrapPoint = cursorValue + requiredCapacity - this.bufferSize;
long cachedGatingSequence = this.gatingSequenceCache.get();
if (wrapPoint > cachedGatingSequence || cachedGatingSequence > cursorValue)
{
long minSequence = Util.getMinimumSequence(gatingSequences, cursorValue);
this.gatingSequenceCache.set(minSequence);
if (wrapPoint > minSequence)
{
return false;
}
}
return true;
}
/**
* @see Sequencer#claim(long)
*/
@Override
public void claim(long sequence)
{
this.cursor.set(sequence);
}
/**
* @see Sequencer#next()
*/
@Override
public long next()
{
return next(1);
}
/**
* @see Sequencer#next(int)
*/
@Override
public long next(int n)
{
if (n < 1)
{
throw new IllegalArgumentException("n must be > 0");
}
long current;
long next;
do
{
current = this.cursor.get();
next = current + n;
long wrapPoint = next - this.bufferSize;
long cachedGatingSequence = this.gatingSequenceCache.get();
if (wrapPoint > cachedGatingSequence || cachedGatingSequence > current)
{
long gatingSequence = Util.getMinimumSequence(this.gatingSequences, current);
if (wrapPoint > gatingSequence)
{
// try {
// waitFor(gatingSequence+1, this.cursor, null, null); // as soon as a spot frees by a consumer, continue
// }
// catch (final AlertException ex)
// {
// if (!this.running.get())
// {
// break;
// }
// } catch (final Throwable ex)
// {
// this.exceptionHandler.handleEventException(ex, next, null);
// break;
// }
LockSupport.parkNanos(1); // TODO, should we spin based on the wait strategy?
continue;
}
this.gatingSequenceCache.set(gatingSequence);
}
else if (this.cursor.compareAndSet(current, next))
{
break;
}
}
while (true);
return next;
}
/**
* @see Sequencer#tryNext()
*/
@Override
public long tryNext() throws InsufficientCapacityException
{
return tryNext(1);
}
/**
* @see Sequencer#tryNext(int)
*/
@Override
public long tryNext(int n) throws InsufficientCapacityException
{
if (n < 1)
{
throw new IllegalArgumentException("n must be > 0");
}
long current;
long next;
do
{
current = this.cursor.get();
next = current + n;
if (!hasAvailableCapacity(this.gatingSequences, n, current))
{
throw InsufficientCapacityException.INSTANCE;
}
}
while (!this.cursor.compareAndSet(current, next));
return next;
}
/**
* @see Sequencer#remainingCapacity()
*/
@Override
public long remainingCapacity()
{
long consumed = Util.getMinimumSequence(this.gatingSequences, this.cursor.get());
long produced = this.cursor.get();
return getBufferSize() - (produced - consumed);
}
private void initialiseAvailableBuffer()
{
for (int i = this.availableBuffer.length - 1; i != 0; i--)
{
setAvailableBufferValue(i, -1);
}
setAvailableBufferValue(0, -1);
}
/**
* @see Sequencer#publish(long)
*/
@Override
public void publish(final long sequence)
{
setAvailable(sequence);
this.waitStrategy.signalAllWhenBlocking();
}
/**
* @see Sequencer#publish(long, long)
*/
@Override
public void publish(long lo, long hi)
{
for (long l = lo; l <= hi; l++)
{
setAvailable(l);
}
this.waitStrategy.signalAllWhenBlocking();
}
/**
* The below methods work on the availableBuffer flag.
*
* The prime reason is to avoid a shared sequence object between publisher threads.
* (Keeping single pointers tracking start and end would require coordination
* between the threads).
*
* -- Firstly we have the constraint that the delta between the cursor and minimum
* gating sequence will never be larger than the buffer size (the code in
* next/tryNext in the Sequence takes care of that).
* -- Given that; take the sequence value and mask off the lower portion of the
* sequence as the index into the buffer (indexMask). (aka modulo operator)
* -- The upper portion of the sequence becomes the value to check for availability.
* ie: it tells us how many times around the ring buffer we've been (aka division)
* -- Because we can't wrap without the gating sequences moving forward (i.e. the
* minimum gating sequence is effectively our last available position in the
* buffer), when we have new data and successfully claimed a slot we can simply
* write over the top.
*/
private void setAvailable(final long sequence)
{
setAvailableBufferValue(calculateIndex(sequence), calculateAvailabilityFlag(sequence));
}
private void setAvailableBufferValue(int index, int flag)
{
long bufferAddress = index * SCALE + BASE;
UNSAFE.putOrderedInt(this.availableBuffer, bufferAddress, flag);
}
/**
* @see Sequencer#isAvailable(long)
*/
@Override
public boolean isAvailable(long sequence)
{
int index = calculateIndex(sequence);
int flag = calculateAvailabilityFlag(sequence);
long bufferAddress = index * SCALE + BASE;
return UNSAFE.getIntVolatile(this.availableBuffer, bufferAddress) == flag;
}
@Override
public long getHighestPublishedSequence(long lowerBound, long availableSequence)
{
for (long sequence = lowerBound; sequence <= availableSequence; sequence++)
{
if (!isAvailable(sequence))
{
return sequence - 1;
}
}
return availableSequence;
}
private int calculateAvailabilityFlag(final long sequence)
{
return (int) (sequence >>> this.indexShift);
}
private int calculateIndex(final long sequence)
{
return (int) sequence & this.indexMask;
}
@Override
public long waitFor(long sequence, Sequence cursorSequence, Sequence dependentSequence, SequenceBarrier barrier)
throws AlertException, InterruptedException
{
long availableSequence;
if ((availableSequence = Util.getMinimumSequence(this.gatingSequences)) < sequence)
{
this.lock.lock();
try
{
while ((availableSequence = Util.getMinimumSequence(this.gatingSequences)) < sequence && this.running.get())
{
this.processorNotifyCondition.await();
}
}
finally
{
this.lock.unlock();
}
}
return availableSequence;
}
@Override
public void signalAllWhenBlocking()
{
this.lock.lock();
try
{
this.processorNotifyCondition.signalAll();
}
finally
{
this.lock.unlock();
}
}
}

208
src/main/java/com/lmax/disruptor/WaitingWorkProcessor.java
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@ -1,208 +0,0 @@
/*
* Copyright 2011 LMAX Ltd.
*
* Licensed 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 com.lmax.disruptor;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* <p>A {@link WaitingWorkProcessor} wraps a single {@link WorkHandler}, effectively consuming the sequence
* and ensuring appropriate barriers.</p>
*
* <p>Generally, this will be used as part of a {@link WaitingWorkerPool}.</p>
*
* @param <T> event implementation storing the details for the work to processed.
*/
public final class WaitingWorkProcessor<T>
implements EventProcessor
{
private final AtomicBoolean running = new AtomicBoolean(false);
private final Sequence sequence = new Sequence(Sequencer.INITIAL_CURSOR_VALUE);
private final RingBuffer<T> ringBuffer;
private final SequenceBarrier sequenceBarrier;
private final WorkHandlerEarlyRelease<? super T> workHandler;
private final ExceptionHandler exceptionHandler;
private final Sequence workSequence;
private final EventReleaser eventReleaser = new EventReleaser()
{
@Override
public void release()
{
WaitingWorkProcessor.this.sequence.set(Long.MAX_VALUE);
}
};
private WaitStrategy publisherStrategy;
/**
* Construct a {@link WaitingWorkProcessor}.
*
* @param ringBuffer to which events are published.
* @param sequenceBarrier on which it is waiting.
* @param sequenceBarrier
* @param workHandler is the delegate to which events are dispatched.
* @param exceptionHandler to be called back when an error occurs
* @param workSequence from which to claim the next event to be worked on. It should always be initialised
* as {@link Sequencer#INITIAL_CURSOR_VALUE}
*/
public WaitingWorkProcessor(final RingBuffer<T> ringBuffer,
final WaitStrategy publisherStrategy,
final SequenceBarrier sequenceBarrier,
final WorkHandlerEarlyRelease<? super T> workHandler,
final ExceptionHandler exceptionHandler,
final Sequence workSequence)
{
this.ringBuffer = ringBuffer;
this.publisherStrategy = publisherStrategy;
this.sequenceBarrier = sequenceBarrier;
this.workHandler = workHandler;
this.exceptionHandler = exceptionHandler;
this.workSequence = workSequence;
if (this.workHandler instanceof EventReleaseAware)
{
((EventReleaseAware)this.workHandler).setEventReleaser(this.eventReleaser);
}
workHandler.setProcessor(this);
}
@Override
public Sequence getSequence()
{
return this.sequence;
}
@Override
public void halt()
{
this.running.set(false);
this.sequenceBarrier.alert();
}
@Override
public boolean isRunning()
{
return this.running.get();
}
/**
* It is ok to have another thread re-run this method after a halt().
*
* @throws IllegalStateException if this processor is already running
*/
@Override
public void run()
{
if (!this.running.compareAndSet(false, true))
{
throw new IllegalStateException("Thread is already running");
}
this.sequenceBarrier.clearAlert();
notifyStart();
WaitStrategy publisherStrategy = this.publisherStrategy;
boolean processedSequence = true;
long cachedAvailableSequence = Long.MIN_VALUE;
long nextSequence = this.sequence.get();
T event = null;
while (true)
{
try
{
// if previous sequence was processed - fetch the next sequence and set
// that we have successfully processed the previous sequence
// typically, this will be true
// this prevents the sequence getting too far forward if an exception
// is thrown from the WorkHandler
if (processedSequence)
{
processedSequence = false;
do
{
nextSequence = this.workSequence.get() + 1L;
// this tells the producer that we are done with our sequence, and that it can reuse it's spot in the ring buffer
this.sequence.set(nextSequence - 1L);
}
while (!this.workSequence.compareAndSet(nextSequence - 1L, nextSequence));
// publisherStrategy.signalAllWhenBlocking();
}
if (cachedAvailableSequence >= nextSequence)
{
event = this.ringBuffer.get(nextSequence);
this.workHandler.onEvent(nextSequence, event);
processedSequence = true;
}
else
{
cachedAvailableSequence = this.sequenceBarrier.waitFor(nextSequence);
}
}
catch (final AlertException ex)
{
if (!this.running.get())
{
break;
}
}
catch (final Throwable ex)
{
// handle, mark as processed, unless the exception handler threw an exception
this.exceptionHandler.handleEventException(ex, nextSequence, event);
processedSequence = true;
}
}
notifyShutdown();
this.running.set(false);
}
private void notifyStart()
{
if (this.workHandler instanceof LifecycleAware)
{
try
{
((LifecycleAware)this.workHandler).onStart();
}
catch (final Throwable ex)
{
this.exceptionHandler.handleOnStartException(ex);
}
}
}
private void notifyShutdown()
{
if (this.workHandler instanceof LifecycleAware)
{
try
{
((LifecycleAware)this.workHandler).onShutdown();
}
catch (final Throwable ex)
{
this.exceptionHandler.handleOnShutdownException(ex);
}
}
}
public void release(long sequence) {
}
}

150
src/main/java/com/lmax/disruptor/WaitingWorkerPool.java
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@ -1,150 +0,0 @@
/*
* Copyright 2011 LMAX Ltd.
*
* Licensed 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 com.lmax.disruptor;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicBoolean;
import com.lmax.disruptor.util.Util;
/**
* WorkerPool contains a pool of {@link WaitingWorkProcessor}s that will consume sequences so jobs can be farmed out across a pool of workers.
* Each of the {@link WaitingWorkProcessor}s manage and calls a {@link WorkHandler} to process the events.
*
* @param <T> event to be processed by a pool of workers
*/
public final class WaitingWorkerPool<T>
{
private final AtomicBoolean started = new AtomicBoolean(false);
private final Sequence workSequence = new Sequence(Sequencer.INITIAL_CURSOR_VALUE);
private final RingBuffer<T> ringBuffer;
// WorkProcessors are created to wrap each of the provided WorkHandlers
private final WaitingWorkProcessor<?>[] workProcessors;
/**
* Create a worker pool to enable an array of {@link WorkHandler}s to consume published sequences.
*
* This option requires a pre-configured {@link RingBuffer} which must have {@link RingBuffer#addGatingSequences(Sequence...)}
* called before the work pool is started.
*
* @param ringBuffer of events to be consumed.
* @param sequenceBarrier on which the workers will depend.
* @param sequenceBarrier2
* @param exceptionHandler to callback when an error occurs which is not handled by the {@link WorkHandler}s.
* @param workHandlers to distribute the work load across.
*/
public WaitingWorkerPool(final RingBuffer<T> ringBuffer,
final WaitStrategy publisherStrategy,
final SequenceBarrier sequenceBarrier,
final ExceptionHandler exceptionHandler,
final WorkHandlerEarlyRelease<? super T>... workHandlers)
{
this.ringBuffer = ringBuffer;
final int numWorkers = workHandlers.length;
this.workProcessors = new WaitingWorkProcessor[numWorkers];
for (int i = 0; i < numWorkers; i++)
{
this.workProcessors[i] = new WaitingWorkProcessor<T>(ringBuffer,
publisherStrategy,
sequenceBarrier,
workHandlers[i],
exceptionHandler,
this.workSequence);
}
}
/**
* Get an array of {@link Sequence}s representing the progress of the workers.
*
* @return an array of {@link Sequence}s representing the progress of the workers.
*/
public Sequence[] getWorkerSequences()
{
// final Sequence[] sequences = new Sequence[this.workProcessors.length + 1];
final Sequence[] sequences = new Sequence[this.workProcessors.length];
for (int i = 0, size = this.workProcessors.length; i < size; i++)
{
sequences[i] = this.workProcessors[i].getSequence();
}
// sequences[sequences.length - 1] = this.workSequence;
return sequences;
}
/**
* Start the worker pool processing events in sequence.
*
* @param executor providing threads for running the workers.
* @return the {@link RingBuffer} used for the work queue.
* @throws IllegalStateException if the pool has already been started and not halted yet
*/
public RingBuffer<T> start(final Executor executor)
{
if (!this.started.compareAndSet(false, true))
{
throw new IllegalStateException("WorkerPool has already been started and cannot be restarted until halted.");
}
final long cursor = this.ringBuffer.getCursor();
this.workSequence.set(cursor);
for (WaitingWorkProcessor<?> processor : this.workProcessors)
{
processor.getSequence().set(cursor);
executor.execute(processor);
}
return this.ringBuffer;
}
/**
* Wait for the {@link RingBuffer} to drain of published events then halt the workers.
*/
public void drainAndHalt()
{
Sequence[] workerSequences = getWorkerSequences();
while (this.ringBuffer.getCursor() > Util.getMinimumSequence(workerSequences))
{
Thread.yield();
}
for (WaitingWorkProcessor<?> processor : this.workProcessors)
{
processor.halt();
}
this.started.set(false);
}
/**
* Halt all workers immediately at the end of their current cycle.
*/
public void halt()
{
for (WaitingWorkProcessor<?> processor : this.workProcessors)
{
processor.halt();
}
this.started.set(false);
}
public boolean isRunning()
{
return this.started.get();
}
}

37
src/main/java/com/lmax/disruptor/WorkHandlerEarlyRelease.java
View File

@ -1,37 +0,0 @@
/*
* Copyright 2011 LMAX Ltd.
*
* Licensed 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 com.lmax.disruptor;
import com.lmax.disruptor.RingBuffer;
/**
* Callback interface to be implemented for processing units of work as they become available in the {@link RingBuffer}.
*
* @param <T> event implementation storing the data for sharing during exchange or parallel coordination of an event.
* @see WaitingWorkerPool
*/
public interface WorkHandlerEarlyRelease<T>
{
/**
* Callback to indicate a unit of work needs to be processed.
*
* @param event published to the {@link RingBuffer}
* @throws Exception if the {@link WorkHandlerEarlyRelease} would like the exception handled further up the chain.
*/
void onEvent(long sequence, T event) throws Exception;
void setProcessor(WaitingWorkProcessor workProcessor);
}

82
src/main/java/dorkbox/util/messagebus/MultiMBassador.java
View File

@ -9,8 +9,8 @@ import dorkbox.util.messagebus.common.DeadMessage;
import dorkbox.util.messagebus.common.ISetEntry;
import dorkbox.util.messagebus.common.NamedThreadFactory;
import dorkbox.util.messagebus.common.StrongConcurrentSetV8;
import dorkbox.util.messagebus.common.simpleq.jctools.MpmcTransferArrayQueue;
import dorkbox.util.messagebus.common.simpleq.jctools.Pow2;
import dorkbox.util.messagebus.common.simpleq.jctools.SimpleQueue;
import dorkbox.util.messagebus.error.IPublicationErrorHandler;
import dorkbox.util.messagebus.error.PublicationError;
import dorkbox.util.messagebus.subscription.Subscription;
@ -29,12 +29,12 @@ public class MultiMBassador implements IMessageBus {
private final Collection<IPublicationErrorHandler> errorHandlers = new ArrayDeque<IPublicationErrorHandler>();
// private final TransferQueue<Runnable> dispatchQueue;
private final SimpleQueue dispatchQueue;
private final MpmcTransferArrayQueue dispatchQueue;
private final SubscriptionManager subscriptionManager;
// all threads that are available for asynchronous message dispatching
private final int numberOfThreads;
// private final int numberOfThreads;
private final Collection<Thread> threads;
/**
@ -72,10 +72,10 @@ public class MultiMBassador implements IMessageBus {
}
numberOfThreads = Pow2.roundToPowerOfTwo(numberOfThreads);
this.numberOfThreads = numberOfThreads;
// this.numberOfThreads = numberOfThreads;
// this.dispatchQueue = new LinkedTransferQueue<Runnable>();
this.dispatchQueue = new SimpleQueue(numberOfThreads);
this.dispatchQueue = new MpmcTransferArrayQueue(numberOfThreads);
this.subscriptionManager = new SubscriptionManager(numberOfThreads);
this.threads = new ArrayDeque<Thread>(numberOfThreads);
@ -86,7 +86,7 @@ public class MultiMBassador implements IMessageBus {
Runnable runnable = new Runnable() {
@Override
public void run() {
SimpleQueue IN_QUEUE = MultiMBassador.this.dispatchQueue;
MpmcTransferArrayQueue IN_QUEUE = MultiMBassador.this.dispatchQueue;
// TransferQueue<Runnable> IN_QUEUE = MultiMBassador.this.dispatchQueue;
Object message1;
@ -417,15 +417,15 @@ public class MultiMBassador implements IMessageBus {
@Override
public void publishAsync(final Object message1, final Object message2) {
if (message1 != null && message2 != null) {
Runnable runnable = new Runnable() {
@Override
public void run() {
MultiMBassador.this.publish(message1, message2);
}
};
// Runnable runnable = new Runnable() {
// @Override
// public void run() {
// MultiMBassador.this.publish(message1, message2);
// }
// };
// try {
this.dispatchQueue.transfer(runnable);
// this.dispatchQueue.transfer(runnable);
// } catch (InterruptedException e) {
// handlePublicationError(new PublicationError()
// .setMessage("Error while adding an asynchronous message")
@ -438,16 +438,16 @@ public class MultiMBassador implements IMessageBus {
@Override
public void publishAsync(final Object message1, final Object message2, final Object message3) {
if (message1 != null || message2 != null | message3 != null) {
Runnable runnable = new Runnable() {
@Override
public void run() {
MultiMBassador.this.publish(message1, message2, message3);
}
};
// Runnable runnable = new Runnable() {
// @Override
// public void run() {
// MultiMBassador.this.publish(message1, message2, message3);
// }
// };
// try {
this.dispatchQueue.transfer(runnable);
// this.dispatchQueue.transfer(runnable);
// } catch (InterruptedException e) {
// handlePublicationError(new PublicationError()
// .setMessage("Error while adding an asynchronous message")
@ -460,15 +460,15 @@ public class MultiMBassador implements IMessageBus {
@Override
public void publishAsync(long timeout, TimeUnit unit, final Object message) {
if (message != null) {
Runnable runnable = new Runnable() {
@Override
public void run() {
MultiMBassador.this.publish(message);
}
};
// Runnable runnable = new Runnable() {
// @Override
// public void run() {
// MultiMBassador.this.publish(message);
// }
// };
// try {
this.dispatchQueue.tryTransfer(runnable, timeout, unit);
// this.dispatchQueue.tryTransfer(runnable, timeout, unit);
// } catch (InterruptedException e) {
// handlePublicationError(new PublicationError()
// .setMessage("Error while adding an asynchronous message")
@ -480,15 +480,15 @@ public class MultiMBassador implements IMessageBus {
@Override
public void publishAsync(long timeout, TimeUnit unit, final Object message1, final Object message2) {
if (message1 != null && message2 != null) {
Runnable runnable = new Runnable() {
@Override
public void run() {
MultiMBassador.this.publish(message1, message2);
}
};
// Runnable runnable = new Runnable() {
// @Override
// public void run() {
// MultiMBassador.this.publish(message1, message2);
// }
// };
// try {
this.dispatchQueue.tryTransfer(runnable, timeout, unit);
// this.dispatchQueue.tryTransfer(runnable, timeout, unit);
// } catch (InterruptedException e) {
// handlePublicationError(new PublicationError()
// .setMessage("Error while adding an asynchronous message")
@ -502,15 +502,15 @@ public class MultiMBassador implements IMessageBus {
@Override
public void publishAsync(long timeout, TimeUnit unit, final Object message1, final Object message2, final Object message3) {
if (message1 != null && message2 != null && message3 != null) {
Runnable runnable = new Runnable() {
@Override
public void run() {
MultiMBassador.this.publish(message1, message2, message3);
}
};
// Runnable runnable = new Runnable() {
// @Override
// public void run() {
// MultiMBassador.this.publish(message1, message2, message3);
// }
// };
// try {
this.dispatchQueue.tryTransfer(runnable, timeout, unit);
// this.dispatchQueue.tryTransfer(runnable, timeout, unit);
// } catch (InterruptedException e) {
// handlePublicationError(new PublicationError()
// .setMessage("Error while adding an asynchronous message")

7
src/main/java/dorkbox/util/messagebus/common/ReflectionUtils.java
View File

@ -17,10 +17,12 @@ import dorkbox.util.messagebus.annotations.Handler;
public class ReflectionUtils {
public static StrongConcurrentSetV8<Method> getMethods(Class<?> target) {
return getMethods(target, new StrongConcurrentSetV8<Method>(16, .8F, 1));
StrongConcurrentSetV8<Method> hashSet = new StrongConcurrentSetV8<Method>(16, .8F, 1);
getMethods(target, hashSet);
return hashSet;
}
public static StrongConcurrentSetV8<Method> getMethods(Class<?> target, StrongConcurrentSetV8<Method> methods) {
private static void getMethods(Class<?> target, StrongConcurrentSetV8<Method> methods) {
try {
for (Method method : target.getDeclaredMethods()) {
if (getAnnotation(method, Handler.class) != null) {
@ -33,7 +35,6 @@ public class ReflectionUtils {
if (!target.equals(Object.class)) {
getMethods(target.getSuperclass(), methods);
}
return methods;
}
/**

2
src/main/java/com/lmax/disruptor/MessageType.java → src/main/java/dorkbox/util/messagebus/common/simpleq/MessageType.java
View File

@ -1,4 +1,4 @@
package com.lmax.disruptor;
package dorkbox.util.messagebus.common.simpleq;
/**
* @author dorkbox, llc
* Date: 2/2/15

226
src/main/java/dorkbox/util/messagebus/common/simpleq/jctools/MpmcArrayTransferQueue.java
View File

@ -1,226 +0,0 @@
package dorkbox.util.messagebus.common.simpleq.jctools;
import java.util.concurrent.ThreadLocalRandom;
public final class MpmcArrayTransferQueue extends MpmcArrayQueueConsumerField<Node> {
/** The number of CPUs */
private static final boolean MP = Runtime.getRuntime().availableProcessors() > 1;
/**
* The number of times to spin (with randomly interspersed calls
* to Thread.yield) on multiprocessor before blocking when a node
* is apparently the first waiter in the queue. See above for
* explanation. Must be a power of two. The value is empirically
* derived -- it works pretty well across a variety of processors,
* numbers of CPUs, and OSes.
*/
private static final int FRONT_SPINS = 1 << 7;
/**
* The number of times to spin before blocking when a node is
* preceded by another node that is apparently spinning. Also
* serves as an increment to FRONT_SPINS on phase changes, and as
* base average frequency for yielding during spins. Must be a
* power of two.
*/
private static final int CHAINED_SPINS = FRONT_SPINS >>> 1;
long p40, p41, p42, p43, p44, p45, p46;
long p30, p31, p32, p33, p34, p35, p36, p37;
/** Creates a {@code EliminationStack} that is initially empty. */
public MpmcArrayTransferQueue(final int size) {
super(size);
}
/**
*
* @param item
* @param timed
* @param nanos
* @return the offset that the item was placed into
*/
public void put(final Object item, final boolean timed, final long nanos) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long capacity = mask + 1;
final long[] sBuffer = this.sequenceBuffer;
long producerIndex;
long pSeqOffset;
long consumerIndex = Long.MAX_VALUE;// start with bogus value, hope we don't need it
while (true) {
producerIndex = lvProducerIndex(); // LoadLoad
pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, item);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
return;
}
// failed cas, retry 1
} else if (delta < 0 && // poll has not moved this value forward
producerIndex - capacity <= consumerIndex && // test against cached cIndex
producerIndex - capacity <= (consumerIndex = lvConsumerIndex())) { // test against latest cIndex
// Extra check required to ensure [Queue.offer == false iff queue is full]
// return false;
}
// another producer has moved the sequence by one, retry 2
busySpin();
}
}
public Object take(final boolean timed, final long nanos) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long cSeqOffset;
long producerIndex = -1; // start with bogus value, hope we don't need it
while (true) {
consumerIndex = lvConsumerIndex(); // LoadLoad
cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
return e;
}
// failed cas, retry 1
} else if (delta < 0 && // slot has not been moved by producer
consumerIndex >= producerIndex && // test against cached pIndex
consumerIndex == (producerIndex = lvProducerIndex())) { // update pIndex if we must
// strict empty check, this ensures [Queue.poll() == null iff isEmpty()]
// return null;
busySpin(); // empty, so busy spin
}
// another consumer beat us and moved sequence ahead, retry 2
busySpin();
}
}
private static final void busySpin() {
ThreadLocalRandom randomYields = ThreadLocalRandom.current();
// busy spin for the amount of time (roughly) of a CPU context switch
// int spins = spinsFor();
int spins = CHAINED_SPINS;
for (;;) {
if (spins > 0) {
if (randomYields.nextInt(CHAINED_SPINS) == 0) {
// LockSupport.parkNanos(1); // occasionally yield
// Thread.yield();
break;
}
--spins;
} else {
break;
}
}
}
/**
* Returns spin/yield value for a node with given predecessor and
* data mode. See above for explanation.
*/
private final static int spinsFor() {
// if (MP && pred != null) {
// if (previousNodeType != currentNodeType) {
// // in the process of changing modes
// return FRONT_SPINS + CHAINED_SPINS;
// }
// if (pred.isMatched()) {
// at the front of the queue
return FRONT_SPINS;
// }
// if (pred.waiter == null) {
// // previous is spinning
// return CHAINED_SPINS;
// }
// }
//
// return 0;
}
@Override
public boolean offer(Node message) {
return false;
}
@Override
public Node poll() {
return null;
}
@Override
public Node peek() {
return null;
}
// public int peekLast() {
// long currConsumerIndex;
// long currProducerIndex;
//
// while (true) {
// currConsumerIndex = lvConsumerIndex();
// currProducerIndex = lvProducerIndex();
//
// if (currConsumerIndex == currProducerIndex) {
// return TYPE_EMPTY;
// }
//
// final Object lpElementNoCast = lpElementNoCast(calcElementOffset(currConsumerIndex));
// if (lpElementNoCast == null) {
// continue;
// }
//
// return lpType(lpElementNoCast);
// }
// }
@Override
public int size() {
return 0;
}
@Override
public boolean isEmpty() {
// Order matters!
// Loading consumer before producer allows for producer increments after consumer index is read.
// This ensures this method is conservative in it's estimate. Note that as this is an MPMC there is
// nothing we can do to make this an exact method.
return lvConsumerIndex() == lvProducerIndex();
}
}

968
src/main/java/dorkbox/util/messagebus/common/simpleq/jctools/MpmcTransferArrayQueue.java Normal file
View File

@ -0,0 +1,968 @@
package dorkbox.util.messagebus.common.simpleq.jctools;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lpItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lpThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lpType;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lvItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lvThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.soItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.soThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.spItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.spThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.spType;
import static dorkbox.util.messagebus.common.simpleq.jctools.UnsafeAccess.UNSAFE;
import java.util.Collection;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TransferQueue;
public final class MpmcTransferArrayQueue extends MpmcArrayQueueConsumerField<Object> implements TransferQueue<Object> {
private static final int TYPE_EMPTY = 0;
private static final int TYPE_CONSUMER = 1;
private static final int TYPE_PRODUCER = 2;
/** Is it multi-processor? */
private static final boolean MP = Runtime.getRuntime().availableProcessors() > 1;
private static int INPROGRESS_SPINS = MP ? 32 : 0;
private static int PUSH_SPINS = MP ? 512 : 0;
private static int POP_SPINS = MP ? 512 : 0;
/**
* The number of times to spin before blocking in timed waits.
* The value is empirically derived -- it works well across a
* variety of processors and OSes. Empirically, the best value
* seems not to vary with number of CPUs (beyond 2) so is just
* a constant.
*/
private static int PARK_TIMED_SPINS = MP ? 32 : 0;
/**
* The number of times to spin before blocking in untimed waits.
* This is greater than timed value because untimed waits spin
* faster since they don't need to check times on each spin.
*/
private static int PARK_UNTIMED_SPINS = PARK_TIMED_SPINS * 16;
/**
* The number of nanoseconds for which it is faster to spin
* rather than to use timed park. A rough estimate suffices.
*/
private static final long SPIN_THRESHOLD = 1000L;
private final int consumerCount;
public MpmcTransferArrayQueue(final int consumerCount) {
this(consumerCount, (int) Math.pow(Runtime.getRuntime().availableProcessors(),2));
}
public MpmcTransferArrayQueue(final int consumerCount, final int queueSize) {
super(Pow2.roundToPowerOfTwo(queueSize));
this.consumerCount = consumerCount;
}
private final static ThreadLocal<Object> nodeThreadLocal = new ThreadLocal<Object>() {
@Override
protected Object initialValue() {
return new Node();
}
};
/**
* PRODUCER method
* <p>
* Place an item on the queue, and wait (if necessary) for a corresponding consumer to take it. This will wait as long as necessary.
*/
@Override
public final void transfer(final Object item) {
producerWait(item, false, 0L);
}
/**
* CONSUMER
*/
@Override
public final Object take() {
return consumerWait(false, 0L);
}
@Override
public boolean offer(Object item) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long capacity = mask + 1;
final long[] sBuffer = this.sequenceBuffer;
long producerIndex;
long pSeqOffset;
long consumerIndex = Long.MAX_VALUE;// start with bogus value, hope we don't need it
while (true) {
producerIndex = lvProducerIndex(); // LoadLoad
pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, item);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
return true;
}
// failed cas, retry 1
} else if (delta < 0 && // poll has not moved this value forward
producerIndex - capacity <= consumerIndex && // test against cached cIndex
producerIndex - capacity <= (consumerIndex = lvConsumerIndex())) { // test against latest cIndex
// Extra check required to ensure [Queue.offer == false iff queue is full]
return false;
}
// another producer has moved the sequence by one, retry 2
busySpin(PUSH_SPINS);
}
}
@Override
public boolean offer(Object item, long timeout, TimeUnit unit) throws InterruptedException {
long nanos = unit.toNanos(timeout);
long lastTime = System.nanoTime();
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long capacity = mask + 1;
final long[] sBuffer = this.sequenceBuffer;
long producerIndex;
long pSeqOffset;
long consumerIndex = Long.MAX_VALUE;// start with bogus value, hope we don't need it
while (true) {
producerIndex = lvProducerIndex(); // LoadLoad
pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, item);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
return true;
}
// failed cas, retry 1
} else if (delta < 0 && // poll has not moved this value forward
producerIndex - capacity <= consumerIndex && // test against cached cIndex
producerIndex - capacity <= (consumerIndex = lvConsumerIndex())) { // test against latest cIndex
// Extra check required to ensure [Queue.offer == false iff queue is full]
long now = System.nanoTime();
long remaining = nanos -= now - lastTime;
lastTime = now;
if (remaining > 0) {
if (remaining < SPIN_THRESHOLD) {
busySpin(PARK_UNTIMED_SPINS);
} else {
UNSAFE.park(false, 1L);
}
} else {
return false;
}
}
// another producer has moved the sequence by one, retry 2
busySpin(PUSH_SPINS);
}
}
@Override
public void put(Object item) throws InterruptedException {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long capacity = mask + 1;
final long[] sBuffer = this.sequenceBuffer;
long producerIndex;
long pSeqOffset;
long consumerIndex = Long.MAX_VALUE;// start with bogus value, hope we don't need it
while (true) {
producerIndex = lvProducerIndex(); // LoadLoad
pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, item);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
return;
}
// failed cas, retry 1
} else if (delta < 0 && // poll has not moved this value forward
producerIndex - capacity <= consumerIndex && // test against cached cIndex
producerIndex - capacity <= (consumerIndex = lvConsumerIndex())) { // test against latest cIndex
// Extra check required to ensure [Queue.offer == false iff queue is full]
// return false;
busySpin(PUSH_SPINS);
}
// another producer has moved the sequence by one, retry 2
busySpin(PUSH_SPINS);
}
}
@Override
public Object poll() {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long cSeqOffset;
long producerIndex = -1; // start with bogus value, hope we don't need it
while (true) {
consumerIndex = lvConsumerIndex(); // LoadLoad
cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
return e;
}
// failed cas, retry 1
} else if (delta < 0 && // slot has not been moved by producer
consumerIndex >= producerIndex && // test against cached pIndex
consumerIndex == (producerIndex = lvProducerIndex())) { // update pIndex if we must
// strict empty check, this ensures [Queue.poll() == null iff isEmpty()]
return null;
}
// another consumer beat us and moved sequence ahead, retry 2
busySpin(POP_SPINS);
}
}
@Override
public final boolean isEmpty() {
// Order matters!
// Loading consumer before producer allows for producer increments after consumer index is read.
// This ensures this method is conservative in it's estimate. Note that as this is an MPMC there is
// nothing we can do to make this an exact method.
return lvConsumerIndex() == lvProducerIndex();
}
@Override
public Object peek() {
long currConsumerIndex;
Object e;
do {
currConsumerIndex = lvConsumerIndex();
// other consumers may have grabbed the element, or queue might be empty
e = lpElementNoCast(calcElementOffset(currConsumerIndex));
// only return null if queue is empty
} while (e == null && currConsumerIndex != lvProducerIndex());
return e;
}
@Override
public int size() {
/*
* It is possible for a thread to be interrupted or reschedule between the read of the producer and
* consumer indices, therefore protection is required to ensure size is within valid range. In the
* event of concurrent polls/offers to this method the size is OVER estimated as we read consumer
* index BEFORE the producer index.
*/
long after = lvConsumerIndex();
while (true) {
final long before = after;
final long currentProducerIndex = lvProducerIndex();
after = lvConsumerIndex();
if (before == after) {
return (int) (currentProducerIndex - after);
}
}
}
@Override
public boolean tryTransfer(Object item) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long producerIndex;
int lastType;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
lastType = TYPE_EMPTY;
previousElement = null;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
lastType = lpType(previousElement);
}
switch (lastType) {
case TYPE_EMPTY:
case TYPE_PRODUCER: {
// empty or same mode = push+park onto queue
long pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
return false;
}
// whoops, inconsistent state
busySpin(PUSH_SPINS);
continue;
}
case TYPE_CONSUMER: {
// complimentary mode = pop+unpark off queue
long cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
soItem1(e, item);
unpark(e);
return true;
}
}
// whoops, inconsistent state
busySpin(POP_SPINS);
continue;
}
}
}
}
@Override
public boolean tryTransfer(Object item, long timeout, TimeUnit unit) throws InterruptedException {
long nanos = unit.toNanos(timeout);
long lastTime = System.nanoTime();
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long producerIndex;
int lastType;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
lastType = TYPE_EMPTY;
previousElement = null;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
lastType = lpType(previousElement);
}
switch (lastType) {
case TYPE_EMPTY:
case TYPE_PRODUCER: {
// empty or same mode = push+park onto queue
long pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
long now = System.nanoTime();
long remaining = nanos -= now - lastTime;
lastTime = now;
if (remaining > 0) {
if (remaining < SPIN_THRESHOLD) {
busySpin(PARK_UNTIMED_SPINS);
} else {
UNSAFE.park(false, 1L);
}
// make sure to continue here (so we don't spin twice)
continue;
} else {
return false;
}
}
// whoops, inconsistent state
busySpin(PUSH_SPINS);
continue;
}
case TYPE_CONSUMER: {
// complimentary mode = pop+unpark off queue
long cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
soItem1(e, item);
unpark(e);
return true;
}
}
// whoops, inconsistent state
busySpin(POP_SPINS);
continue;
}
}
}
}
@Override
public Object poll(long timeout, TimeUnit unit) throws InterruptedException {
long nanos = unit.toNanos(timeout);
long lastTime = System.nanoTime();
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long cSeqOffset;
long producerIndex = -1; // start with bogus value, hope we don't need it
while (true) {
consumerIndex = lvConsumerIndex(); // LoadLoad
cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
return e;
}
// failed cas, retry 1
} else if (delta < 0 && // slot has not been moved by producer
consumerIndex >= producerIndex && // test against cached pIndex
consumerIndex == (producerIndex = lvProducerIndex())) { // update pIndex if we must
// strict empty check, this ensures [Queue.poll() == null iff isEmpty()]
long now = System.nanoTime();
long remaining = nanos -= now - lastTime;
lastTime = now;
if (remaining > 0) {
if (remaining < SPIN_THRESHOLD) {
busySpin(PARK_UNTIMED_SPINS);
} else {
UNSAFE.park(false, 1L);
}
// make sure to continue here (so we don't spin twice)
continue;
} else {
return null;
}
}
// another consumer beat us and moved sequence ahead, retry 2
busySpin(POP_SPINS);
}
}
@Override
public int remainingCapacity() {
// TODO Auto-generated method stub
return 0;
}
@Override
public int drainTo(Collection c) {
// TODO Auto-generated method stub
return 0;
}
@Override
public int drainTo(Collection c, int maxElements) {
// TODO Auto-generated method stub
return 0;
}
@Override
public Object[] toArray(Object[] a) {
// TODO Auto-generated method stub
return null;
}
@Override
public boolean containsAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean addAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean removeAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean retainAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean hasWaitingConsumer() {
long consumerIndex;
long producerIndex;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
return false;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
return lpType(previousElement) == TYPE_CONSUMER;
}
}
}
@Override
public int getWaitingConsumerCount() {
long consumerIndex;
long producerIndex;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
return 0;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
if (lpType(previousElement) == TYPE_CONSUMER) {
return (int) (producerIndex - consumerIndex);
} else {
return 0;
}
}
}
}
public final boolean hasPendingMessages() {
long consumerIndex;
long producerIndex;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
return true;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
return lpType(previousElement) != TYPE_CONSUMER || consumerIndex + this.consumerCount != producerIndex;
}
}
}
private static final void busySpin(int spins) {
for (;;) {
if (spins > 0) {
--spins;
} else {
return;
}
}
}
@SuppressWarnings("null")
private final void park(final Object node, final Thread myThread, final boolean timed, long nanos) {
long lastTime = timed ? System.nanoTime() : 0L;
int spins = -1; // initialized after first item and cancel checks
ThreadLocalRandom randomYields = null; // bound if needed
for (;;) {
if (lvThread(node) == null) {
return;
} else if (myThread.isInterrupted() || timed && nanos <= 0) {
return;
} else if (spins < 0) {
if (timed) {
spins = PARK_TIMED_SPINS;
} else {
spins = PARK_UNTIMED_SPINS;
}
if (spins > 0) {
randomYields = ThreadLocalRandom.current();
}
} else if (spins > 0) {
if (randomYields.nextInt(256) == 0) {
Thread.yield(); // occasionally yield
}
--spins;
} else if (timed) {
long now = System.nanoTime();
long remaining = nanos -= now - lastTime;
lastTime = now;
if (remaining > 0) {
if (remaining < SPIN_THRESHOLD) {
busySpin(PARK_UNTIMED_SPINS);
} else {
UNSAFE.park(false, nanos);
}
} else {
return;
}
} else {
// park can return for NO REASON (must check for thread values)
UNSAFE.park(false, 0L);
}
}
}
private final void unpark(Object node) {
final Object thread = lpThread(node);
soThread(node, null);
UNSAFE.unpark(thread);
}
private final void producerWait(final Object item, final boolean timed, final long nanos) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long producerIndex;
int lastType;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
lastType = TYPE_EMPTY;
previousElement = null;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
lastType = lpType(previousElement);
}
switch (lastType) {
case TYPE_EMPTY:
case TYPE_PRODUCER: {
// empty or same mode = push+park onto queue
long pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
final Thread myThread = Thread.currentThread();
final Object node = nodeThreadLocal.get();
spType(node, TYPE_PRODUCER);
spThread(node, myThread);
spItem1(node, item);
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, node);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
park(node, myThread, timed, nanos);
return;
}
}
// whoops, inconsistent state
busySpin(PUSH_SPINS);
continue;
}
case TYPE_CONSUMER: {
// complimentary mode = pop+unpark off queue
long cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
soItem1(e, item);
unpark(e);
return;
}
}
// whoops, inconsistent state
busySpin(POP_SPINS);
continue;
}
}
}
}
private final Object consumerWait(final boolean timed, final long nanos) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long producerIndex;
int lastType;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
lastType = TYPE_EMPTY;
previousElement = null;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
lastType = lpType(previousElement);
}
switch (lastType) {
case TYPE_EMPTY:
case TYPE_CONSUMER: {
// empty or same mode = push+park onto queue
long pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
final Thread myThread = Thread.currentThread();
final Object node = nodeThreadLocal.get();
spType(node, TYPE_CONSUMER);
spThread(node, myThread);
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, node);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
park(node, myThread, timed, nanos);
Object item1 = lvItem1(node);
return item1;
}
}
// whoops, inconsistent state
busySpin(PUSH_SPINS);
continue;
}
case TYPE_PRODUCER: {
// complimentary mode = pop+unpark off queue
long cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
final Object lvItem1 = lpItem1(e);
unpark(e);
return lvItem1;
}
}
// whoops, inconsistent state
busySpin(POP_SPINS);
continue;
}
}
}
}
}

3
src/main/java/dorkbox/util/messagebus/common/simpleq/jctools/Node.java
View File

@ -1,8 +1,7 @@
package dorkbox.util.messagebus.common.simpleq.jctools;
import static dorkbox.util.messagebus.common.simpleq.jctools.UnsafeAccess.UNSAFE;
import com.lmax.disruptor.MessageType;
import dorkbox.util.messagebus.common.simpleq.MessageType;
abstract class ColdItems {
public int type = 0;

525
src/main/java/dorkbox/util/messagebus/common/simpleq/jctools/SimpleQueue.java
View File

@ -1,525 +0,0 @@
package dorkbox.util.messagebus.common.simpleq.jctools;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lpItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lpThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lpType;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lvItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.lvThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.soItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.soThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.spItem1;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.spThread;
import static dorkbox.util.messagebus.common.simpleq.jctools.Node.spType;
import static dorkbox.util.messagebus.common.simpleq.jctools.UnsafeAccess.UNSAFE;
import java.util.Collection;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TransferQueue;
public final class SimpleQueue extends MpmcArrayQueueConsumerField<Object> implements TransferQueue<Object> {
private static final int TYPE_EMPTY = 0;
private static final int TYPE_CONSUMER = 1;
private static final int TYPE_PRODUCER = 2;
/** Is it multi-processor? */
private static final boolean MP = Runtime.getRuntime().availableProcessors() > 1;
private static int INPROGRESS_SPINS = MP ? 32 : 0;
private static int PUSH_SPINS = MP ? 512 : 0;
private static int POP_SPINS = MP ? 512 : 0;
/**
* The number of times to spin before blocking in timed waits.
* The value is empirically derived -- it works well across a
* variety of processors and OSes. Empirically, the best value
* seems not to vary with number of CPUs (beyond 2) so is just
* a constant.
*/
private static int PARK_TIMED_SPINS = MP ? 32 : 0;
/**
* The number of times to spin before blocking in untimed waits.
* This is greater than timed value because untimed waits spin
* faster since they don't need to check times on each spin.
*/
private static int PARK_UNTIMED_SPINS = PARK_TIMED_SPINS * 16;
/**
* The number of nanoseconds for which it is faster to spin
* rather than to use timed park. A rough estimate suffices.
*/
private static final long SPIN_THRESHOLD = 1000L;
private final int consumerCount;
public SimpleQueue(final int consumerCount) {
super(Pow2.roundToPowerOfTwo(consumerCount*Runtime.getRuntime().availableProcessors()));
this.consumerCount = consumerCount;
}
private final static ThreadLocal<Object> nodeThreadLocal = new ThreadLocal<Object>() {
@Override
protected Object initialValue() {
return new Node();
}
};
/**
* PRODUCER method
* <p>
* Place an item on the queue, and wait (if necessary) for a corresponding consumer to take it. This will wait as long as necessary.
*/
@Override
public final void transfer(final Object item) {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long producerIndex;
int lastType;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
lastType = TYPE_EMPTY;
previousElement = null;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
lastType = lpType(previousElement);
}
switch (lastType) {
case TYPE_EMPTY:
case TYPE_PRODUCER: {
// empty or same mode = push+park onto queue
long pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
final Thread myThread = Thread.currentThread();
final Object node = nodeThreadLocal.get();
spType(node, TYPE_PRODUCER);
spThread(node, myThread);
spItem1(node, item);
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, node);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
park(node, myThread, false, 0);
return;
}
}
// whoops, inconsistent state
busySpin(PUSH_SPINS);
continue;
}
case TYPE_CONSUMER: {
// complimentary mode = pop+unpark off queue
long cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
soItem1(e, item);
unpark(e);
return;
}
}
// whoops, inconsistent state
busySpin(POP_SPINS);
continue;
}
}
}
}
/**
* CONSUMER
*/
@Override
public final Object take() {
// local load of field to avoid repeated loads after volatile reads
final long mask = this.mask;
final long[] sBuffer = this.sequenceBuffer;
long consumerIndex;
long producerIndex;
int lastType;
while (true) {
consumerIndex = lvConsumerIndex();
producerIndex = lvProducerIndex();
final Object previousElement;
if (consumerIndex == producerIndex) {
lastType = TYPE_EMPTY;
previousElement = null;
} else {
previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement == null) {
// the last producer hasn't finished setting the object yet
busySpin(INPROGRESS_SPINS);
continue;
}
lastType = lpType(previousElement);
}
switch (lastType) {
case TYPE_EMPTY:
case TYPE_CONSUMER: {
// empty or same mode = push+park onto queue
long pSeqOffset = calcSequenceOffset(producerIndex, mask);
final long seq = lvSequence(sBuffer, pSeqOffset); // LoadLoad
final long delta = seq - producerIndex;
if (delta == 0) {
// this is expected if we see this first time around
if (casProducerIndex(producerIndex, producerIndex + 1)) {
// Successful CAS: full barrier
final Thread myThread = Thread.currentThread();
final Object node = nodeThreadLocal.get();
spType(node, TYPE_CONSUMER);
spThread(node, myThread);
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(producerIndex, mask);
spElement(offset, node);
// increment sequence by 1, the value expected by consumer
// (seeing this value from a producer will lead to retry 2)
soSequence(sBuffer, pSeqOffset, producerIndex + 1); // StoreStore
park(node, myThread, false, 0);
Object item1 = lvItem1(node);
return item1;
}
}
// whoops, inconsistent state
busySpin(PUSH_SPINS);
continue;
}
case TYPE_PRODUCER: {
// complimentary mode = pop+unpark off queue
long cSeqOffset = calcSequenceOffset(consumerIndex, mask);
final long seq = lvSequence(sBuffer, cSeqOffset); // LoadLoad
final long delta = seq - (consumerIndex + 1);
if (delta == 0) {
if (casConsumerIndex(consumerIndex, consumerIndex + 1)) {
// Successful CAS: full barrier
// on 64bit(no compressed oops) JVM this is the same as seqOffset
final long offset = calcElementOffset(consumerIndex, mask);
final Object e = lpElementNoCast(offset);
spElement(offset, null);
// Move sequence ahead by capacity, preparing it for next offer
// (seeing this value from a consumer will lead to retry 2)
soSequence(sBuffer, cSeqOffset, consumerIndex + mask + 1); // StoreStore
final Object lvItem1 = lpItem1(e);
unpark(e);
return lvItem1;
}
}
// whoops, inconsistent state
busySpin(POP_SPINS);
continue;
}
}
}
}
private static final void busySpin(int spins) {
for (;;) {
if (spins > 0) {
--spins;
} else {
return;
}
}
}
@SuppressWarnings("null")
private final void park(final Object node, final Thread myThread, final boolean timed, long nanos) {
long lastTime = timed ? System.nanoTime() : 0L;
int spins = -1; // initialized after first item and cancel checks
ThreadLocalRandom randomYields = null; // bound if needed
for (;;) {
if (lvThread(node) == null) {
return;
} else if (myThread.isInterrupted() || timed && nanos <= 0) {
return;
} else if (spins < 0) {
if (timed) {
spins = PARK_TIMED_SPINS;
} else {
spins = PARK_UNTIMED_SPINS;
}
if (spins > 0) {
randomYields = ThreadLocalRandom.current();
}
} else if (spins > 0) {
if (randomYields.nextInt(256) == 0) {
Thread.yield(); // occasionally yield
}
--spins;
} else if (timed) {
long now = System.nanoTime();
long remaining = nanos -= now - lastTime;
if (remaining > 0) {
if (remaining < SPIN_THRESHOLD) {
busySpin(PARK_UNTIMED_SPINS);
} else {
UNSAFE.park(false, nanos);
}
}
lastTime = now;
} else {
// park can return for NO REASON (must check for thread values)
UNSAFE.park(false, 0L);
}
}
}
private final void unpark(Object node) {
final Object thread = lpThread(node);
soThread(node, null);
UNSAFE.unpark(thread);
}
@Override
public final boolean isEmpty() {
// Order matters!
// Loading consumer before producer allows for producer increments after consumer index is read.
// This ensures this method is conservative in it's estimate. Note that as this is an MPMC there is
// nothing we can do to make this an exact method.
return lvConsumerIndex() == lvProducerIndex();
}
public final boolean hasPendingMessages() {
// count the number of consumers waiting, it should be the same as the number of threads configured
long consumerIndex = lvConsumerIndex();
long producerIndex = lvProducerIndex();
if (consumerIndex != producerIndex) {
final Object previousElement = lpElementNoCast(calcElementOffset(producerIndex-1));
if (previousElement != null && lpType(previousElement) == TYPE_CONSUMER && consumerIndex + this.consumerCount == producerIndex) {
return false;
}
}
return true;
}
public void tryTransfer(Runnable runnable, long timeout, TimeUnit unit) {
}
@Override
public boolean offer(Object message) {
// TODO Auto-generated method stub
return false;
}
@Override
public Object poll() {
// TODO Auto-generated method stub
return null;
}
@Override
public Object peek() {
long currConsumerIndex;
Object e;
do {
currConsumerIndex = lvConsumerIndex();
// other consumers may have grabbed the element, or queue might be empty
e = lpElementNoCast(calcElementOffset(currConsumerIndex));
// only return null if queue is empty
} while (e == null && currConsumerIndex != lvProducerIndex());
return e;
}
@Override
public int size() {
/*
* It is possible for a thread to be interrupted or reschedule between the read of the producer and
* consumer indices, therefore protection is required to ensure size is within valid range. In the
* event of concurrent polls/offers to this method the size is OVER estimated as we read consumer
* index BEFORE the producer index.
*/
long after = lvConsumerIndex();
while (true) {
final long before = after;
final long currentProducerIndex = lvProducerIndex();
after = lvConsumerIndex();
if (before == after) {
return (int) (currentProducerIndex - after);
}
}
}
@Override
public void put(Object e) throws InterruptedException {
// TODO Auto-generated method stub
}
@Override
public boolean offer(Object e, long timeout, TimeUnit unit) throws InterruptedException {
// TODO Auto-generated method stub
return false;
}
@Override
public Object poll(long timeout, TimeUnit unit) throws InterruptedException {
// TODO Auto-generated method stub
return null;
}
@Override
public int remainingCapacity() {
// TODO Auto-generated method stub
return 0;
}
@Override
public int drainTo(Collection c) {
// TODO Auto-generated method stub
return 0;
}
@Override
public int drainTo(Collection c, int maxElements) {
// TODO Auto-generated method stub
return 0;
}
@Override
public Object[] toArray(Object[] a) {
// TODO Auto-generated method stub
return null;
}
@Override
public boolean containsAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean addAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean removeAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean retainAll(Collection c) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean tryTransfer(Object e) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean tryTransfer(Object e, long timeout, TimeUnit unit) throws InterruptedException {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean hasWaitingConsumer() {
// TODO Auto-generated method stub
return false;
}
@Override
public int getWaitingConsumerCount() {
// TODO Auto-generated method stub
return 0;
}
}

42
src/test/java/dorkbox/util/messagebus/MpmcQueueAltConcurrentPerfTest.java → src/test/java/dorkbox/util/messagebus/LinkTransferQueueConcurrentNonBlockPerfTest.java
View File

@ -1,41 +1,39 @@
/*
* Copyright 2012 Real Logic Ltd.
*
* Licensed 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
* Licensed 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.
* 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 dorkbox.util.messagebus;
import java.util.concurrent.LinkedTransferQueue;
import org.openjdk.jol.info.ClassLayout;
import org.openjdk.jol.util.VMSupport;
import dorkbox.util.messagebus.common.simpleq.jctools.MpmcArrayTransferQueue;
import dorkbox.util.messagebus.common.simpleq.jctools.Node;
public class MpmcQueueAltConcurrentPerfTest {
public class LinkTransferQueueConcurrentNonBlockPerfTest {
// 15 == 32 * 1024
public static final int REPETITIONS = Integer.getInteger("reps", 50) * 1000 * 100;
public static final Integer TEST_VALUE = Integer.valueOf(777);
public static final int QUEUE_CAPACITY = 1 << Integer.getInteger("pow2.capacity", 17);
private static final int concurrency = 2;
private static final int concurrency = 4;
public static void main(final String[] args) throws Exception {
System.out.println(VMSupport.vmDetails());
System.out.println(ClassLayout.parseClass(Node.class).toPrintable());
System.out.println("capacity:" + QUEUE_CAPACITY + " reps:" + REPETITIONS + " Concurrency " + concurrency);
final MpmcArrayTransferQueue queue = new MpmcArrayTransferQueue(1 << 17);
final LinkedTransferQueue queue = new LinkedTransferQueue();
final long[] results = new long[20];
for (int i = 0; i < 20; i++) {
@ -50,7 +48,7 @@ public class MpmcQueueAltConcurrentPerfTest {
System.out.format("summary,QueuePerfTest,%s %,d\n", queue.getClass().getSimpleName(), sum / 10);
}
private static long performanceRun(int runNumber, MpmcArrayTransferQueue queue) throws Exception {
private static long performanceRun(int runNumber, LinkedTransferQueue queue) throws Exception {
Producer[] producers = new Producer[concurrency];
Consumer[] consumers = new Consumer[concurrency];
@ -99,42 +97,44 @@ public class MpmcQueueAltConcurrentPerfTest {
}
public static class Producer implements Runnable {
private final MpmcArrayTransferQueue queue;
private final LinkedTransferQueue queue;
volatile long start;
public Producer(MpmcArrayTransferQueue queue) {
public Producer(LinkedTransferQueue queue) {
this.queue = queue;
}
@Override
public void run() {
MpmcArrayTransferQueue producer = this.queue;
LinkedTransferQueue producer = this.queue;
int i = REPETITIONS;
this.start = System.nanoTime();
do {
producer.put(TEST_VALUE, false, 0);
producer.put(TEST_VALUE);
} while (0 != --i);
}
}
public static class Consumer implements Runnable {
private final MpmcArrayTransferQueue queue;
private final LinkedTransferQueue queue;
Object result;
volatile long end;
public Consumer(MpmcArrayTransferQueue queue) {
public Consumer(LinkedTransferQueue queue) {
this.queue = queue;
}
@Override
public void run() {
MpmcArrayTransferQueue consumer = this.queue;
LinkedTransferQueue consumer = this.queue;
Object result = null;
int i = REPETITIONS;
do {
result = consumer.take(false, 0);
while((result = consumer.poll()) == null) {
Thread.yield();
}
} while (0 != --i);
this.result = result;

167
src/test/java/dorkbox/util/messagebus/MpmcNonBlockPerfTest.java Normal file
View File

@ -0,0 +1,167 @@
package dorkbox.util.messagebus;
import org.openjdk.jol.info.ClassLayout;
import org.openjdk.jol.util.VMSupport;
import dorkbox.util.messagebus.common.simpleq.jctools.MpmcTransferArrayQueue;
import dorkbox.util.messagebus.common.simpleq.jctools.Node;
public class MpmcNonBlockPerfTest {
public static final int REPETITIONS = 50 * 1000 * 100;
public static final Integer TEST_VALUE = Integer.valueOf(777);
public static final int QUEUE_CAPACITY = 1 << 17;
private static final int concurrency = 4;
public static void main(final String[] args) throws Exception {
System.out.println(VMSupport.vmDetails());
System.out.println(ClassLayout.parseClass(Node.class).toPrintable());
System.out.println("capacity:" + QUEUE_CAPACITY + " reps:" + REPETITIONS + " Concurrency " + concurrency);
final int warmupRuns = 2;
final int runs = 5;
long average = 0;
final MpmcTransferArrayQueue queue = new MpmcTransferArrayQueue(QUEUE_CAPACITY);
average = averageRun(warmupRuns, runs, queue);
// SimpleQueue.INPROGRESS_SPINS = 64;
// SimpleQueue.POP_SPINS = 512;
// SimpleQueue.PUSH_SPINS = 512;
// SimpleQueue.PARK_SPINS = 512;
//
// for (int i = 128; i< 10000;i++) {
// int full = 2*i;
//
// final SimpleQueue queue = new SimpleQueue(QUEUE_CAPACITY);
// SimpleQueue.PARK_SPINS = full;
//
//
// long newAverage = averageRun(warmupRuns, runs, queue);
// if (newAverage > average) {
// average = newAverage;
// System.err.println("Best value: " + i + " : " + newAverage);
// }
// }
System.out.format("summary,QueuePerfTest,%s %,d\n", queue.getClass().getSimpleName(), average);
}
private static long averageRun(int warmUpRuns, int sumCount, MpmcTransferArrayQueue queue) throws Exception {
int runs = warmUpRuns + sumCount;
final long[] results = new long[runs];
for (int i = 0; i < runs; i++) {
System.gc();
results[i] = performanceRun(i, queue);
}
// only average last X results for summary
long sum = 0;
for (int i = warmUpRuns; i < runs; i++) {
sum += results[i];
}
return sum/sumCount;
}
private static long performanceRun(int runNumber, MpmcTransferArrayQueue queue) throws Exception {
Producer[] producers = new Producer[concurrency];
Consumer[] consumers = new Consumer[concurrency];
Thread[] threads = new Thread[concurrency*2];
for (int i=0;i<concurrency;i++) {
producers[i] = new Producer(queue);
consumers[i] = new Consumer(queue);
}
for (int j=0,i=0;i<concurrency;i++,j+=2) {
threads[j] = new Thread(producers[i], "Producer " + i);
threads[j+1] = new Thread(consumers[i], "Consumer " + i);
}
for (int i=0;i<concurrency*2;i+=2) {
threads[i].start();
threads[i+1].start();
}
for (int i=0;i<concurrency*2;i+=2) {
threads[i].join();
threads[i+1].join();
}
long start = Long.MAX_VALUE;
long end = -1;
for (int i=0;i<concurrency;i++) {
if (producers[i].start < start) {
start = producers[i].start;
}
if (consumers[i].end > end) {
end = consumers[i].end;
}
}
long duration = end - start;
long ops = REPETITIONS * 1_000_000_000L / duration;
String qName = queue.getClass().getSimpleName();
System.out.format("%d - ops/sec=%,d - %s\n", runNumber, ops, qName);
return ops;
}
public static class Producer implements Runnable {
private final MpmcTransferArrayQueue queue;
volatile long start;
public Producer(MpmcTransferArrayQueue queue) {
this.queue = queue;
}
@Override
public void run() {
MpmcTransferArrayQueue producer = this.queue;
int i = REPETITIONS;
this.start = System.nanoTime();
try {
do {
producer.put(TEST_VALUE);
} while (0 != --i);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
public static class Consumer implements Runnable {
private final MpmcTransferArrayQueue queue;
Object result;
volatile long end;
public Consumer(MpmcTransferArrayQueue queue) {
this.queue = queue;
}
@Override
public void run() {
MpmcTransferArrayQueue consumer = this.queue;
Object result = null;
int i = REPETITIONS;
do {
while((result = consumer.poll()) == null) {
Thread.yield();
}
} while (0 != --i);
this.result = result;
this.end = System.nanoTime();
}
}
}

103
src/test/java/dorkbox/util/messagebus/MpmcQueueAltPerfTest.java
View File

@ -1,103 +0,0 @@
/*
* Copyright 2012 Real Logic Ltd.
*
* Licensed 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 dorkbox.util.messagebus;
import org.openjdk.jol.info.ClassLayout;
import org.openjdk.jol.util.VMSupport;
import dorkbox.util.messagebus.common.simpleq.jctools.MpmcArrayQueue;
import dorkbox.util.messagebus.common.simpleq.jctools.MpmcArrayTransferQueue;
import dorkbox.util.messagebus.common.simpleq.jctools.Node;
public class MpmcQueueAltPerfTest {
// 15 == 32 * 1024
public static final int REPETITIONS = Integer.getInteger("reps", 50) * 1000 * 100;
public static final Integer TEST_VALUE = Integer.valueOf(777);
public static final int QUEUE_CAPACITY = 1 << Integer.getInteger("pow2.capacity", 17);
public static void main(final String[] args) throws Exception {
System.out.println(VMSupport.vmDetails());
System.out.println(ClassLayout.parseClass(Node.class).toPrintable());
System.out.println("capacity:" + QUEUE_CAPACITY + " reps:" + REPETITIONS);
final MpmcArrayTransferQueue queue = new MpmcArrayTransferQueue(QUEUE_CAPACITY);
final long[] results = new long[20];
for (int i = 0; i < 20; i++) {
System.gc();
results[i] = performanceRun(i, queue);
}
// only average last 10 results for summary
long sum = 0;
for (int i = 10; i < 20; i++) {
sum += results[i];
}
System.out.format("summary,QueuePerfTest,%s,%d\n", queue.getClass().getSimpleName(), sum / 10);
}
private static long performanceRun(int runNumber, MpmcArrayTransferQueue queue) throws Exception {
Producer p = new Producer(queue);
Thread thread = new Thread(p);
thread.start(); // producer will timestamp start
MpmcArrayTransferQueue consumer = queue;
Object result;
int i = REPETITIONS;
do {
result = consumer.take(false, 0);
} while (0 != --i);
long end = System.nanoTime();
thread.join();
long duration = end - p.start;
long ops = REPETITIONS * 1000L * 1000L * 1000L / duration;
String qName = queue.getClass().getSimpleName();
System.out.format("%d - ops/sec=%,d - %s result=%d\n", runNumber, ops, qName, ((Node)result).item1);
return ops;
}
public static class Producer implements Runnable {
private final MpmcArrayTransferQueue queue;
long start;
public Producer(MpmcArrayTransferQueue queue) {
this.queue = queue;
}
@Override
public void run() {
MpmcArrayTransferQueue producer = this.queue;
int i = REPETITIONS;
long s = System.nanoTime();
MpmcArrayQueue<Node> pool = new MpmcArrayQueue<Node>(2);
pool.offer(new Node());
pool.offer(new Node());
Node node;
do {
node = pool.poll();
node.item1 = TEST_VALUE;
producer.put(node, false, 0);
pool.offer(node);
} while (0 != --i);
this.start = s;
}
}
}

22
src/test/java/dorkbox/util/messagebus/SimpleQueueAltPerfTest.java → src/test/java/dorkbox/util/messagebus/MpmcTransferPerfTest.java
View File

@ -3,10 +3,10 @@ package dorkbox.util.messagebus;
import org.openjdk.jol.info.ClassLayout;
import org.openjdk.jol.util.VMSupport;
import dorkbox.util.messagebus.common.simpleq.jctools.MpmcTransferArrayQueue;
import dorkbox.util.messagebus.common.simpleq.jctools.Node;
import dorkbox.util.messagebus.common.simpleq.jctools.SimpleQueue;
public class SimpleQueueAltPerfTest {
public class MpmcTransferPerfTest {
public static final int REPETITIONS = 50 * 1000 * 100;
public static final Integer TEST_VALUE = Integer.valueOf(777);
@ -25,7 +25,7 @@ public class SimpleQueueAltPerfTest {
long average = 0;
final SimpleQueue queue = new SimpleQueue(QUEUE_CAPACITY);
final MpmcTransferArrayQueue queue = new MpmcTransferArrayQueue(QUEUE_CAPACITY);
average = averageRun(warmupRuns, runs, queue);
// SimpleQueue.INPROGRESS_SPINS = 64;
@ -51,7 +51,7 @@ public class SimpleQueueAltPerfTest {
System.out.format("summary,QueuePerfTest,%s %,d\n", queue.getClass().getSimpleName(), average);
}
private static long averageRun(int warmUpRuns, int sumCount, SimpleQueue queue) throws Exception {
private static long averageRun(int warmUpRuns, int sumCount, MpmcTransferArrayQueue queue) throws Exception {
int runs = warmUpRuns + sumCount;
final long[] results = new long[runs];
for (int i = 0; i < runs; i++) {
@ -67,7 +67,7 @@ public class SimpleQueueAltPerfTest {
return sum/sumCount;
}
private static long performanceRun(int runNumber, SimpleQueue queue) throws Exception {
private static long performanceRun(int runNumber, MpmcTransferArrayQueue queue) throws Exception {
Producer[] producers = new Producer[concurrency];
Consumer[] consumers = new Consumer[concurrency];
@ -116,16 +116,16 @@ public class SimpleQueueAltPerfTest {
}
public static class Producer implements Runnable {
private final SimpleQueue queue;
private final MpmcTransferArrayQueue queue;
volatile long start;
public Producer(SimpleQueue queue) {
public Producer(MpmcTransferArrayQueue queue) {
this.queue = queue;
}
@Override
public void run() {
SimpleQueue producer = this.queue;
MpmcTransferArrayQueue producer = this.queue;
int i = REPETITIONS;
this.start = System.nanoTime();
@ -136,17 +136,17 @@ public class SimpleQueueAltPerfTest {
}
public static class Consumer implements Runnable {
private final SimpleQueue queue;
private final MpmcTransferArrayQueue queue;
Object result;
volatile long end;
public Consumer(SimpleQueue queue) {
public Consumer(MpmcTransferArrayQueue queue) {
this.queue = queue;
}
@Override
public void run() {
SimpleQueue consumer = this.queue;
MpmcTransferArrayQueue consumer = this.queue;
Object result = null;
int i = REPETITIONS;