org.eclipse.jetty.io.MappedByteBufferPool Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995 Mort Bay Consulting Pty Ltd and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
// ========================================================================
//
package org.eclipse.jetty.io;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Function;
import org.eclipse.jetty.util.BufferUtil;
import org.eclipse.jetty.util.NanoTime;
import org.eclipse.jetty.util.annotation.ManagedAttribute;
import org.eclipse.jetty.util.annotation.ManagedObject;
import org.eclipse.jetty.util.component.Dumpable;
import org.eclipse.jetty.util.component.DumpableCollection;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A ByteBuffer pool where ByteBuffers are held in queues that are held in a Map.
* Given a capacity {@code factor} of 1024, the Map entry with key {@code 1} holds a
* queue of ByteBuffers each of capacity 1024, the Map entry with key {@code 2} holds a
* queue of ByteBuffers each of capacity 2048, and so on.
*/
@ManagedObject
public class MappedByteBufferPool extends AbstractByteBufferPool implements Dumpable
{
private static final Logger LOG = LoggerFactory.getLogger(MappedByteBufferPool.class);
private final ConcurrentMap _directBuffers = new ConcurrentHashMap<>();
private final ConcurrentMap _heapBuffers = new ConcurrentHashMap<>();
private final Function _newBucket;
private boolean _detailedDump = false;
/**
* Creates a new MappedByteBufferPool with a default configuration.
*/
public MappedByteBufferPool()
{
this(-1);
}
/**
* Creates a new MappedByteBufferPool with the given capacity factor.
*
* @param factor the capacity factor
*/
public MappedByteBufferPool(int factor)
{
this(factor, -1);
}
/**
* Creates a new MappedByteBufferPool with the given configuration.
*
* @param factor the capacity factor
* @param maxBucketSize the maximum ByteBuffer bucket size
*/
public MappedByteBufferPool(int factor, int maxBucketSize)
{
this(factor, maxBucketSize, null);
}
/**
* Creates a new MappedByteBufferPool with the given configuration.
*
* @param factor the capacity factor
* @param maxBucketSize the maximum ByteBuffer bucket size
* @param newBucket the function that creates a Bucket
*/
private MappedByteBufferPool(int factor, int maxBucketSize, Function newBucket)
{
this(factor, maxBucketSize, newBucket, 0, 0, 0, 0);
}
/**
* Creates a new MappedByteBufferPool with the given configuration.
*
* @param factor the capacity factor
* @param maxBucketSize the maximum ByteBuffer bucket size
* @param maxHeapMemory the max heap memory in bytes, -1 for unlimited memory or 0 to use default heuristic.
* @param maxDirectMemory the max direct memory in bytes, -1 for unlimited memory or 0 to use default heuristic.
*/
public MappedByteBufferPool(int factor, int maxBucketSize, long maxHeapMemory, long maxDirectMemory)
{
this(factor, maxBucketSize, null, maxHeapMemory, maxDirectMemory, maxHeapMemory, maxDirectMemory);
}
/**
* Creates a new MappedByteBufferPool with the given configuration.
*
* @param factor the capacity factor
* @param maxBucketSize the maximum ByteBuffer bucket size
* @param maxHeapMemory the max heap memory in bytes, -1 for unlimited memory or 0 to use default heuristic.
* @param maxDirectMemory the max direct memory in bytes, -1 for unlimited memory or 0 to use default heuristic.
* @param retainedHeapMemory the max heap memory in bytes, -2 for no retained memory, -1 for unlimited retained memory or 0 to use default heuristic
* @param retainedDirectMemory the max direct memory in bytes, -2 for no retained memory, -1 for unlimited retained memory or 0 to use default heuristic
*/
public MappedByteBufferPool(int factor, int maxBucketSize, long maxHeapMemory, long maxDirectMemory, long retainedHeapMemory, long retainedDirectMemory)
{
this(factor, maxBucketSize, null, maxHeapMemory, maxDirectMemory, retainedHeapMemory, retainedDirectMemory);
}
/**
* Creates a new MappedByteBufferPool with the given configuration.
*
* @param factor the capacity factor
* @param maxBucketSize the maximum ByteBuffer bucket size
* @param newBucket the function that creates a Bucket
* @param maxHeapMemory the max heap memory in bytes, -1 for unlimited memory or 0 to use default heuristic.
* @param maxDirectMemory the max direct memory in bytes, -1 for unlimited memory or 0 to use default heuristic.
* @param retainedHeapMemory the max heap memory in bytes, -2 for no retained memory, -1 for unlimited retained memory or 0 to use default heuristic
* @param retainedDirectMemory the max direct memory in bytes, -2 for no retained memory, -1 for unlimited retained memory or 0 to use default heuristic
*/
private MappedByteBufferPool(int factor, int maxBucketSize, Function newBucket, long maxHeapMemory, long maxDirectMemory, long retainedHeapMemory, long retainedDirectMemory)
{
super(factor, 0, maxBucketSize, maxHeapMemory, maxDirectMemory, retainedHeapMemory, retainedDirectMemory);
_newBucket = newBucket;
}
@Override
protected RetainableByteBufferPool newRetainableByteBufferPool(int factor, int maxCapacity, int maxBucketSize, long retainedHeapMemory, long retainedDirectMemory)
{
return new Retained(factor, maxCapacity, maxBucketSize, retainedHeapMemory, retainedDirectMemory);
}
private Bucket newBucket(int key, boolean direct)
{
return (_newBucket != null) ? _newBucket.apply(key) : new Bucket(capacityFor(key), getMaxBucketSize(), updateMemory(direct));
}
@Override
public ByteBuffer acquire(int size, boolean direct)
{
int b = bucketFor(size);
int capacity = capacityFor(b);
ConcurrentMap buffers = bucketsFor(direct);
Bucket bucket = buffers.get(b);
if (bucket == null)
return newByteBuffer(capacity, direct);
ByteBuffer buffer = bucket.acquire();
if (buffer == null)
return newByteBuffer(capacity, direct);
return buffer;
}
@Override
public void release(ByteBuffer buffer)
{
if (buffer == null)
return; // nothing to do
int capacity = buffer.capacity();
int b = bucketFor(capacity);
// Validate that this buffer is from this pool.
if (capacity != capacityFor(b))
{
if (LOG.isDebugEnabled())
LOG.debug("ByteBuffer {} does not belong to this pool, discarding it", BufferUtil.toDetailString(buffer));
return;
}
boolean direct = buffer.isDirect();
ConcurrentMap buckets = bucketsFor(direct);
Bucket bucket = buckets.computeIfAbsent(b, i -> newBucket(i, direct));
bucket.release(buffer);
releaseExcessMemory(direct, this::releaseMemory);
}
@Override
public void clear()
{
super.clear();
_directBuffers.values().forEach(Bucket::clear);
_directBuffers.clear();
_heapBuffers.values().forEach(Bucket::clear);
_heapBuffers.clear();
}
protected void releaseMemory(boolean direct)
{
long oldest = Long.MAX_VALUE;
int index = -1;
ConcurrentMap buckets = bucketsFor(direct);
for (Map.Entry entry : buckets.entrySet())
{
Bucket bucket = entry.getValue();
if (bucket.isEmpty())
continue;
long lastUpdateNanoTime = bucket.getLastUpdate();
if (oldest == Long.MAX_VALUE || NanoTime.isBefore(lastUpdateNanoTime, oldest))
{
oldest = lastUpdateNanoTime;
index = entry.getKey();
}
}
if (index >= 0)
{
Bucket bucket = buckets.remove(index);
// Null guard in case this.clear() is called concurrently.
if (bucket != null)
bucket.clear();
}
}
protected int bucketFor(int capacity)
{
return (int)Math.ceil((double)capacity / getCapacityFactor());
}
protected int capacityFor(int bucket)
{
return bucket * getCapacityFactor();
}
@ManagedAttribute("The number of pooled direct ByteBuffers")
public long getDirectByteBufferCount()
{
return getByteBufferCount(true);
}
@ManagedAttribute("The number of pooled heap ByteBuffers")
public long getHeapByteBufferCount()
{
return getByteBufferCount(false);
}
private long getByteBufferCount(boolean direct)
{
return bucketsFor(direct).values().stream()
.mapToLong(Bucket::size)
.sum();
}
// Package local for testing
ConcurrentMap bucketsFor(boolean direct)
{
return direct ? _directBuffers : _heapBuffers;
}
public static class Tagged extends MappedByteBufferPool
{
private final AtomicInteger tag = new AtomicInteger();
@Override
public ByteBuffer newByteBuffer(int capacity, boolean direct)
{
ByteBuffer buffer = super.newByteBuffer(capacity + 4, direct);
buffer.limit(buffer.capacity());
buffer.putInt(tag.incrementAndGet());
ByteBuffer slice = buffer.slice();
BufferUtil.clear(slice);
return slice;
}
}
public boolean isDetailedDump()
{
return _detailedDump;
}
public void setDetailedDump(boolean detailedDump)
{
_detailedDump = detailedDump;
}
@Override
public void dump(Appendable out, String indent) throws IOException
{
List