PoolThreadCache.java — netty Source File

Source Code

/*
 * Copyright 2012 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.PoolArena.SizeClass;
import io.netty.util.Recycler;
import io.netty.util.Recycler.EnhancedHandle;
import io.netty.util.internal.MathUtil;
import io.netty.util.internal.ObjectPool.Handle;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;

import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.Queue;
import java.util.concurrent.atomic.AtomicBoolean;

import static io.netty.util.internal.ObjectUtil.checkPositiveOrZero;

/**
 * Acts a Thread cache for allocations. This implementation is moduled after
 * <a href="https://people.freebsd.org/~jasone/jemalloc/bsdcan2006/jemalloc.pdf">jemalloc</a> and the descripted
 * technics of
 * <a href="https://www.facebook.com/notes/facebook-engineering/scalable-memory-allocation-using-jemalloc/480222803919">
 * Scalable memory allocation using jemalloc</a>.
 */
final class PoolThreadCache {

    private static final InternalLogger logger = InternalLoggerFactory.getInstance(PoolThreadCache.class);
    private static final int INTEGER_SIZE_MINUS_ONE = Integer.SIZE - 1;

    final PoolArena<byte[]> heapArena;
    final PoolArena<ByteBuffer> directArena;

    // Hold the caches for the different size classes, which are small and normal.
    private final MemoryRegionCache<byte[]>[] smallSubPageHeapCaches;
    private final MemoryRegionCache<ByteBuffer>[] smallSubPageDirectCaches;
    private final MemoryRegionCache<byte[]>[] normalHeapCaches;
    private final MemoryRegionCache<ByteBuffer>[] normalDirectCaches;

    private final int freeSweepAllocationThreshold;
    private final AtomicBoolean freed = new AtomicBoolean();
    @SuppressWarnings("unused") // Field is only here for the finalizer.
// ... (440 more lines)