io.netty.buffer.AdaptiveByteBufAllocator Maven / Gradle / Ivy
/*
* Copyright 2024 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* https://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 io.netty.buffer;
import io.netty.buffer.AdaptivePoolingAllocator.MagazineCaching;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.SystemPropertyUtil;
import io.netty.util.internal.UnstableApi;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import static io.netty.util.internal.PlatformDependent.javaVersion;
/**
* An auto-tuning pooling {@link ByteBufAllocator}, that follows an anti-generational hypothesis.
*
* Note: this allocator is experimental. It is recommended to roll out usage slowly,
* and to carefully monitor application performance in the process.
*
* See the {@link AdaptivePoolingAllocator} class documentation for implementation details.
*/
@UnstableApi
public final class AdaptiveByteBufAllocator extends AbstractByteBufAllocator
implements ByteBufAllocatorMetricProvider, ByteBufAllocatorMetric {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(AdaptiveByteBufAllocator.class);
private static final boolean DEFAULT_USE_CACHED_MAGAZINES_FOR_NON_EVENT_LOOP_THREADS;
static {
DEFAULT_USE_CACHED_MAGAZINES_FOR_NON_EVENT_LOOP_THREADS = SystemPropertyUtil.getBoolean(
"io.netty.allocator.useCachedMagazinesForNonEventLoopThreads", false);
logger.debug("-Dio.netty.allocator.useCachedMagazinesForNonEventLoopThreads: {}",
DEFAULT_USE_CACHED_MAGAZINES_FOR_NON_EVENT_LOOP_THREADS);
}
private final AdaptiveAllocatorApi direct;
private final AdaptiveAllocatorApi heap;
public AdaptiveByteBufAllocator() {
this(PlatformDependent.directBufferPreferred());
}
public AdaptiveByteBufAllocator(boolean preferDirect) {
this(preferDirect, DEFAULT_USE_CACHED_MAGAZINES_FOR_NON_EVENT_LOOP_THREADS);
}
public AdaptiveByteBufAllocator(boolean preferDirect, boolean useCacheForNonEventLoopThreads) {
super(preferDirect);
if (javaVersion() < 8) {
// The implementation uses StampedLock, which was introduced in Java 8.
throw new IllegalStateException("This allocator require Java 8 or newer.");
}
MagazineCaching magazineCaching = useCacheForNonEventLoopThreads?
MagazineCaching.FastThreadLocalThreads : MagazineCaching.EventLoopThreads;
direct = new AdaptivePoolingAllocator(new DirectChunkAllocator(this), magazineCaching);
heap = new AdaptivePoolingAllocator(new HeapChunkAllocator(this), magazineCaching);
}
@Override
protected ByteBuf newHeapBuffer(int initialCapacity, int maxCapacity) {
return heap.allocate(initialCapacity, maxCapacity);
}
@Override
protected ByteBuf newDirectBuffer(int initialCapacity, int maxCapacity) {
return direct.allocate(initialCapacity, maxCapacity);
}
@Override
public boolean isDirectBufferPooled() {
return true;
}
@Override
public long usedHeapMemory() {
return heap.usedMemory();
}
@Override
public long usedDirectMemory() {
return direct.usedMemory();
}
@Override
public ByteBufAllocatorMetric metric() {
return this;
}
interface AdaptiveAllocatorApi {
ByteBuf allocate(int initialCapacity, int maxCapacity);
long usedMemory();
}
private static final class HeapChunkAllocator implements AdaptivePoolingAllocator.ChunkAllocator {
private final ByteBufAllocator allocator;
private HeapChunkAllocator(ByteBufAllocator allocator) {
this.allocator = allocator;
}
@Override
public ByteBuf allocate(int initialCapacity, int maxCapacity) {
return PlatformDependent.hasUnsafe() ?
new UnpooledUnsafeHeapByteBuf(allocator, initialCapacity, maxCapacity) :
new UnpooledHeapByteBuf(allocator, initialCapacity, maxCapacity);
}
}
private static final class DirectChunkAllocator implements AdaptivePoolingAllocator.ChunkAllocator {
private final ByteBufAllocator allocator;
private DirectChunkAllocator(ByteBufAllocator allocator) {
this.allocator = allocator;
}
@Override
public ByteBuf allocate(int initialCapacity, int maxCapacity) {
return PlatformDependent.hasUnsafe() ?
UnsafeByteBufUtil.newUnsafeDirectByteBuf(allocator, initialCapacity, maxCapacity) :
new UnpooledDirectByteBuf(allocator, initialCapacity, maxCapacity);
}
}
}