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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including
all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and
Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* 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:
*
* 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 io.netty.buffer;
import io.netty.buffer.PoolArena.SizeClass;
import io.netty.util.Recycler;
import io.netty.util.Recycler.Handle;
import io.netty.util.internal.MathUtil;
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.Queue;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* Acts a Thread cache for allocations. This implementation is moduled after
* jemalloc and the descripted
* technics of
*
* Scalable memory allocation using jemalloc.
*/
final class PoolThreadCache {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(PoolThreadCache.class);
final PoolArena heapArena;
final PoolArena directArena;
// Hold the caches for the different size classes, which are tiny, small and normal.
private final MemoryRegionCache[] tinySubPageHeapCaches;
private final MemoryRegionCache[] smallSubPageHeapCaches;
private final MemoryRegionCache[] tinySubPageDirectCaches;
private final MemoryRegionCache[] smallSubPageDirectCaches;
private final MemoryRegionCache[] normalHeapCaches;
private final MemoryRegionCache[] normalDirectCaches;
// Used for bitshifting when calculate the index of normal caches later
private final int numShiftsNormalDirect;
private final int numShiftsNormalHeap;
private final int freeSweepAllocationThreshold;
private final AtomicBoolean freed = new AtomicBoolean();
private int allocations;
// TODO: Test if adding padding helps under contention
//private long pad0, pad1, pad2, pad3, pad4, pad5, pad6, pad7;
PoolThreadCache(PoolArena heapArena, PoolArena directArena,
int tinyCacheSize, int smallCacheSize, int normalCacheSize,
int maxCachedBufferCapacity, int freeSweepAllocationThreshold) {
if (maxCachedBufferCapacity < 0) {
throw new IllegalArgumentException("maxCachedBufferCapacity: "
+ maxCachedBufferCapacity + " (expected: >= 0)");
}
this.freeSweepAllocationThreshold = freeSweepAllocationThreshold;
this.heapArena = heapArena;
this.directArena = directArena;
if (directArena != null) {
tinySubPageDirectCaches = createSubPageCaches(
tinyCacheSize, PoolArena.numTinySubpagePools, SizeClass.Tiny);
smallSubPageDirectCaches = createSubPageCaches(
smallCacheSize, directArena.numSmallSubpagePools, SizeClass.Small);
numShiftsNormalDirect = log2(directArena.pageSize);
normalDirectCaches = createNormalCaches(
normalCacheSize, maxCachedBufferCapacity, directArena);
directArena.numThreadCaches.getAndIncrement();
} else {
// No directArea is configured so just null out all caches
tinySubPageDirectCaches = null;
smallSubPageDirectCaches = null;
normalDirectCaches = null;
numShiftsNormalDirect = -1;
}
if (heapArena != null) {
// Create the caches for the heap allocations
tinySubPageHeapCaches = createSubPageCaches(
tinyCacheSize, PoolArena.numTinySubpagePools, SizeClass.Tiny);
smallSubPageHeapCaches = createSubPageCaches(
smallCacheSize, heapArena.numSmallSubpagePools, SizeClass.Small);
numShiftsNormalHeap = log2(heapArena.pageSize);
normalHeapCaches = createNormalCaches(
normalCacheSize, maxCachedBufferCapacity, heapArena);
heapArena.numThreadCaches.getAndIncrement();
} else {
// No heapArea is configured so just null out all caches
tinySubPageHeapCaches = null;
smallSubPageHeapCaches = null;
normalHeapCaches = null;
numShiftsNormalHeap = -1;
}
// Only check if there are caches in use.
if ((tinySubPageDirectCaches != null || smallSubPageDirectCaches != null || normalDirectCaches != null
|| tinySubPageHeapCaches != null || smallSubPageHeapCaches != null || normalHeapCaches != null)
&& freeSweepAllocationThreshold < 1) {
throw new IllegalArgumentException("freeSweepAllocationThreshold: "
+ freeSweepAllocationThreshold + " (expected: > 0)");
}
}
private static MemoryRegionCache[] createSubPageCaches(
int cacheSize, int numCaches, SizeClass sizeClass) {
if (cacheSize > 0 && numCaches > 0) {
@SuppressWarnings("unchecked")
MemoryRegionCache[] cache = new MemoryRegionCache[numCaches];
for (int i = 0; i < cache.length; i++) {
// TODO: maybe use cacheSize / cache.length
cache[i] = new SubPageMemoryRegionCache(cacheSize, sizeClass);
}
return cache;
} else {
return null;
}
}
private static MemoryRegionCache[] createNormalCaches(
int cacheSize, int maxCachedBufferCapacity, PoolArena area) {
if (cacheSize > 0 && maxCachedBufferCapacity > 0) {
int max = Math.min(area.chunkSize, maxCachedBufferCapacity);
int arraySize = Math.max(1, log2(max / area.pageSize) + 1);
@SuppressWarnings("unchecked")
MemoryRegionCache[] cache = new MemoryRegionCache[arraySize];
for (int i = 0; i < cache.length; i++) {
cache[i] = new NormalMemoryRegionCache(cacheSize);
}
return cache;
} else {
return null;
}
}
private static int log2(int val) {
int res = 0;
while (val > 1) {
val >>= 1;
res++;
}
return res;
}
/**
* Try to allocate a tiny buffer out of the cache. Returns {@code true} if successful {@code false} otherwise
*/
boolean allocateTiny(PoolArena area, PooledByteBuf buf, int reqCapacity, int normCapacity) {
return allocate(cacheForTiny(area, normCapacity), buf, reqCapacity);
}
/**
* Try to allocate a small buffer out of the cache. Returns {@code true} if successful {@code false} otherwise
*/
boolean allocateSmall(PoolArena area, PooledByteBuf buf, int reqCapacity, int normCapacity) {
return allocate(cacheForSmall(area, normCapacity), buf, reqCapacity);
}
/**
* Try to allocate a small buffer out of the cache. Returns {@code true} if successful {@code false} otherwise
*/
boolean allocateNormal(PoolArena area, PooledByteBuf buf, int reqCapacity, int normCapacity) {
return allocate(cacheForNormal(area, normCapacity), buf, reqCapacity);
}
@SuppressWarnings({ "unchecked", "rawtypes" })
private boolean allocate(MemoryRegionCache cache, PooledByteBuf buf, int reqCapacity) {
if (cache == null) {
// no cache found so just return false here
return false;
}
boolean allocated = cache.allocate(buf, reqCapacity);
if (++ allocations >= freeSweepAllocationThreshold) {
allocations = 0;
trim();
}
return allocated;
}
/**
* Add {@link PoolChunk} and {@code handle} to the cache if there is enough room.
* Returns {@code true} if it fit into the cache {@code false} otherwise.
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
boolean add(PoolArena area, PoolChunk chunk, long handle, int normCapacity, SizeClass sizeClass) {
MemoryRegionCache cache = cache(area, normCapacity, sizeClass);
if (cache == null) {
return false;
}
return cache.add(chunk, handle);
}
private MemoryRegionCache cache(PoolArena area, int normCapacity, SizeClass sizeClass) {
switch (sizeClass) {
case Normal:
return cacheForNormal(area, normCapacity);
case Small:
return cacheForSmall(area, normCapacity);
case Tiny:
return cacheForTiny(area, normCapacity);
default:
throw new Error();
}
}
/// TODO: In the future when we move to Java9+ we should use java.lang.ref.Cleaner.
@Override
protected void finalize() throws Throwable {
try {
super.finalize();
} finally {
free();
}
}
/**
* Should be called if the Thread that uses this cache is about to exist to release resources out of the cache
*/
void free() {
// As free() may be called either by the finalizer or by FastThreadLocal.onRemoval(...) we need to ensure
// we only call this one time.
if (freed.compareAndSet(false, true)) {
int numFreed = free(tinySubPageDirectCaches) +
free(smallSubPageDirectCaches) +
free(normalDirectCaches) +
free(tinySubPageHeapCaches) +
free(smallSubPageHeapCaches) +
free(normalHeapCaches);
if (numFreed > 0 && logger.isDebugEnabled()) {
logger.debug("Freed {} thread-local buffer(s) from thread: {}", numFreed,
Thread.currentThread().getName());
}
if (directArena != null) {
directArena.numThreadCaches.getAndDecrement();
}
if (heapArena != null) {
heapArena.numThreadCaches.getAndDecrement();
}
}
}
private static int free(MemoryRegionCache[] caches) {
if (caches == null) {
return 0;
}
int numFreed = 0;
for (MemoryRegionCache c: caches) {
numFreed += free(c);
}
return numFreed;
}
private static int free(MemoryRegionCache cache) {
if (cache == null) {
return 0;
}
return cache.free();
}
void trim() {
trim(tinySubPageDirectCaches);
trim(smallSubPageDirectCaches);
trim(normalDirectCaches);
trim(tinySubPageHeapCaches);
trim(smallSubPageHeapCaches);
trim(normalHeapCaches);
}
private static void trim(MemoryRegionCache[] caches) {
if (caches == null) {
return;
}
for (MemoryRegionCache c: caches) {
trim(c);
}
}
private static void trim(MemoryRegionCache cache) {
if (cache == null) {
return;
}
cache.trim();
}
private MemoryRegionCache cacheForTiny(PoolArena area, int normCapacity) {
int idx = PoolArena.tinyIdx(normCapacity);
if (area.isDirect()) {
return cache(tinySubPageDirectCaches, idx);
}
return cache(tinySubPageHeapCaches, idx);
}
private MemoryRegionCache cacheForSmall(PoolArena area, int normCapacity) {
int idx = PoolArena.smallIdx(normCapacity);
if (area.isDirect()) {
return cache(smallSubPageDirectCaches, idx);
}
return cache(smallSubPageHeapCaches, idx);
}
private MemoryRegionCache cacheForNormal(PoolArena area, int normCapacity) {
if (area.isDirect()) {
int idx = log2(normCapacity >> numShiftsNormalDirect);
return cache(normalDirectCaches, idx);
}
int idx = log2(normCapacity >> numShiftsNormalHeap);
return cache(normalHeapCaches, idx);
}
private static MemoryRegionCache cache(MemoryRegionCache[] cache, int idx) {
if (cache == null || idx > cache.length - 1) {
return null;
}
return cache[idx];
}
/**
* Cache used for buffers which are backed by TINY or SMALL size.
*/
private static final class SubPageMemoryRegionCache extends MemoryRegionCache {
SubPageMemoryRegionCache(int size, SizeClass sizeClass) {
super(size, sizeClass);
}
@Override
protected void initBuf(
PoolChunk chunk, long handle, PooledByteBuf buf, int reqCapacity) {
chunk.initBufWithSubpage(buf, handle, reqCapacity);
}
}
/**
* Cache used for buffers which are backed by NORMAL size.
*/
private static final class NormalMemoryRegionCache extends MemoryRegionCache {
NormalMemoryRegionCache(int size) {
super(size, SizeClass.Normal);
}
@Override
protected void initBuf(
PoolChunk chunk, long handle, PooledByteBuf buf, int reqCapacity) {
chunk.initBuf(buf, handle, reqCapacity);
}
}
private abstract static class MemoryRegionCache {
private final int size;
private final Queue> queue;
private final SizeClass sizeClass;
private int allocations;
MemoryRegionCache(int size, SizeClass sizeClass) {
this.size = MathUtil.safeFindNextPositivePowerOfTwo(size);
queue = PlatformDependent.newFixedMpscQueue(this.size);
this.sizeClass = sizeClass;
}
/**
* Init the {@link PooledByteBuf} using the provided chunk and handle with the capacity restrictions.
*/
protected abstract void initBuf(PoolChunk chunk, long handle,
PooledByteBuf buf, int reqCapacity);
/**
* Add to cache if not already full.
*/
@SuppressWarnings("unchecked")
public final boolean add(PoolChunk chunk, long handle) {
Entry entry = newEntry(chunk, handle);
boolean queued = queue.offer(entry);
if (!queued) {
// If it was not possible to cache the chunk, immediately recycle the entry
entry.recycle();
}
return queued;
}
/**
* Allocate something out of the cache if possible and remove the entry from the cache.
*/
public final boolean allocate(PooledByteBuf buf, int reqCapacity) {
Entry entry = queue.poll();
if (entry == null) {
return false;
}
initBuf(entry.chunk, entry.handle, buf, reqCapacity);
entry.recycle();
// allocations is not thread-safe which is fine as this is only called from the same thread all time.
++ allocations;
return true;
}
/**
* Clear out this cache and free up all previous cached {@link PoolChunk}s and {@code handle}s.
*/
public final int free() {
return free(Integer.MAX_VALUE);
}
private int free(int max) {
int numFreed = 0;
for (; numFreed < max; numFreed++) {
Entry entry = queue.poll();
if (entry != null) {
freeEntry(entry);
} else {
// all cleared
return numFreed;
}
}
return numFreed;
}
/**
* Free up cached {@link PoolChunk}s if not allocated frequently enough.
*/
public final void trim() {
int free = size - allocations;
allocations = 0;
// We not even allocated all the number that are
if (free > 0) {
free(free);
}
}
@SuppressWarnings({ "unchecked", "rawtypes" })
private void freeEntry(Entry entry) {
PoolChunk chunk = entry.chunk;
long handle = entry.handle;
// recycle now so PoolChunk can be GC'ed.
entry.recycle();
chunk.arena.freeChunk(chunk, handle, sizeClass);
}
static final class Entry {
final Handle> recyclerHandle;
PoolChunk chunk;
long handle = -1;
Entry(Handle> recyclerHandle) {
this.recyclerHandle = recyclerHandle;
}
void recycle() {
chunk = null;
handle = -1;
recyclerHandle.recycle(this);
}
}
@SuppressWarnings("rawtypes")
private static Entry newEntry(PoolChunk chunk, long handle) {
Entry entry = RECYCLER.get();
entry.chunk = chunk;
entry.handle = handle;
return entry;
}
@SuppressWarnings("rawtypes")
private static final Recycler RECYCLER = new Recycler() {
@SuppressWarnings("unchecked")
@Override
protected Entry newObject(Handle handle) {
return new Entry(handle);
}
};
}
}
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