Expose metrics for PooledByteBufAllocator
Motivation: The PooledByteBufAllocator is more or less a black-box atm. We need to expose some metrics to allow the user to get a better idea how to tune it. Modifications: - Expose different metrics via PooledByteBufAllocator - Add *Metrics interfaces Result: It is now easy to gather metrics and detail about the PooledByteBufAllocator and so get a better understanding about resource-usage etc.
This commit is contained in:
Norman Maurer
parent
8a1a0b2c1e
commit
8fed94eee3
@ -16,12 +16,16 @@
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package io.netty.buffer;
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import io.netty.util.internal.LongCounter;
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import io.netty.util.internal.PlatformDependent;
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import io.netty.util.internal.StringUtil;
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import java.nio.ByteBuffer;
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import java.util.ArrayList;
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import java.util.Collections;
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import java.util.List;
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abstract class PoolArena<T> {
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abstract class PoolArena<T> implements PoolArenaMetric {
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static final int numTinySubpagePools = 512 >>> 4;
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@ -43,6 +47,21 @@ abstract class PoolArena<T> {
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private final PoolChunkList<T> q075;
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private final PoolChunkList<T> q100;
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private final List<PoolChunkListMetric> chunkListMetrics;
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// Metrics for allocations and deallocations
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private long allocationsTiny;
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private long allocationsSmall;
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private long allocationsNormal;
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// We need to use the LongCounter here as this is not guarded via synchronized block.
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private final LongCounter allocationsHuge = PlatformDependent.newLongCounter();
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private long deallocationsTiny;
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private long deallocationsSmall;
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private long deallocationsNormal;
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// We need to use the LongCounter here as this is not guarded via synchronized block.
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private final LongCounter deallocationsHuge = PlatformDependent.newLongCounter();
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// TODO: Test if adding padding helps under contention
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//private long pad0, pad1, pad2, pad3, pad4, pad5, pad6, pad7;
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@ -77,6 +96,15 @@ abstract class PoolArena<T> {
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q025.prevList = q000;
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q000.prevList = null;
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qInit.prevList = qInit;
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List<PoolChunkListMetric> metrics = new ArrayList<PoolChunkListMetric>(6);
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metrics.add(qInit);
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metrics.add(q000);
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metrics.add(q025);
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metrics.add(q050);
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metrics.add(q075);
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metrics.add(q100);
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chunkListMetrics = Collections.unmodifiableList(metrics);
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}
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private PoolSubpage<T> newSubpagePoolHead(int pageSize) {
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@ -128,7 +156,8 @@ abstract class PoolArena<T> {
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if (isTinyOrSmall(normCapacity)) { // capacity < pageSize
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int tableIdx;
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PoolSubpage<T>[] table;
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if (isTiny(normCapacity)) { // < 512
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boolean tiny = isTiny(normCapacity);
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if (tiny) { // < 512
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if (cache.allocateTiny(this, buf, reqCapacity, normCapacity)) {
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// was able to allocate out of the cache so move on
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return;
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@ -152,6 +181,12 @@ abstract class PoolArena<T> {
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long handle = s.allocate();
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assert handle >= 0;
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s.chunk.initBufWithSubpage(buf, handle, reqCapacity);
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if (tiny) {
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++allocationsTiny;
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} else {
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++allocationsSmall;
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}
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return;
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}
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allocateNormal(buf, reqCapacity, normCapacity);
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@ -173,6 +208,8 @@ abstract class PoolArena<T> {
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}
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private void allocateNormal(PooledByteBuf<T> buf, int reqCapacity, int normCapacity) {
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++allocationsNormal;
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if (q050.allocate(buf, reqCapacity, normCapacity) || q025.allocate(buf, reqCapacity, normCapacity) ||
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q000.allocate(buf, reqCapacity, normCapacity) || qInit.allocate(buf, reqCapacity, normCapacity) ||
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q075.allocate(buf, reqCapacity, normCapacity) || q100.allocate(buf, reqCapacity, normCapacity)) {
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@ -188,11 +225,13 @@ abstract class PoolArena<T> {
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}
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private void allocateHuge(PooledByteBuf<T> buf, int reqCapacity) {
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allocationsHuge.increment();
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buf.initUnpooled(newUnpooledChunk(reqCapacity), reqCapacity);
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}
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void free(PoolChunk<T> chunk, long handle, int normCapacity, boolean sameThreads) {
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if (chunk.unpooled) {
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allocationsHuge.decrement();
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destroyChunk(chunk);
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} else {
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if (sameThreads) {
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@ -203,7 +242,15 @@ abstract class PoolArena<T> {
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}
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}
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boolean tinyOrSmall = isTinyOrSmall(normCapacity);
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synchronized (this) {
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if (!tinyOrSmall) {
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++deallocationsNormal;
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} else if (isTiny(normCapacity)) {
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++deallocationsTiny;
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} else {
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++deallocationsSmall;
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}
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chunk.parent.free(chunk, handle);
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}
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}
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@ -306,12 +353,142 @@ abstract class PoolArena<T> {
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}
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}
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@Override
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public int numTinySubpages() {
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return tinySubpagePools.length;
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}
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@Override
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public int numSmallSubpages() {
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return smallSubpagePools.length;
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}
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@Override
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public int numChunkLists() {
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return chunkListMetrics.size();
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}
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@Override
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public List<PoolSubpageMetric> tinySubpages() {
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return subPageMetricList(tinySubpagePools);
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}
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@Override
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public List<PoolSubpageMetric> smallSubpages() {
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return subPageMetricList(smallSubpagePools);
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}
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@Override
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public List<PoolChunkListMetric> chunkLists() {
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return chunkListMetrics;
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}
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private static List<PoolSubpageMetric> subPageMetricList(PoolSubpage<?>[] pages) {
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List<PoolSubpageMetric> metrics = new ArrayList<PoolSubpageMetric>();
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for (int i = 1; i < pages.length; i ++) {
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PoolSubpage<?> head = pages[i];
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if (head.next == head) {
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continue;
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}
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PoolSubpage<?> s = head.next;
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for (;;) {
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metrics.add(s);
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s = s.next;
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if (s == head) {
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break;
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}
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}
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}
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return metrics;
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}
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@Override
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public long numAllocations() {
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return allocationsTiny + allocationsSmall + allocationsNormal + allocationsHuge.value();
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}
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@Override
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public long numTinyAllocations() {
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return allocationsTiny;
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}
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@Override
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public long numSmallAllocations() {
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return allocationsSmall;
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}
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@Override
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public long numNormalAllocations() {
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return allocationsNormal;
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}
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@Override
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public long numDeallocations() {
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return deallocationsTiny + deallocationsSmall + allocationsNormal + deallocationsHuge.value();
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}
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@Override
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public long numTinyDeallocations() {
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return deallocationsTiny;
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}
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@Override
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public long numSmallDeallocations() {
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return deallocationsSmall;
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}
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@Override
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public long numNormalDeallocations() {
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return deallocationsNormal;
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}
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@Override
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public long numHugeAllocations() {
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return allocationsHuge.value();
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}
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@Override
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public long numHugeDeallocations() {
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return deallocationsHuge.value();
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}
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@Override
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public long numActiveAllocations() {
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long val = numAllocations() - numDeallocations();
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return val >= 0 ? val : 0;
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}
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@Override
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public long numActiveTinyAllocations() {
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long val = numTinyAllocations() - numTinyDeallocations();
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return val >= 0 ? val : 0;
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}
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@Override
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public long numActiveSmallAllocations() {
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long val = numSmallAllocations() - numSmallDeallocations();
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return val >= 0 ? val : 0;
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}
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@Override
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public long numActiveNormalAllocations() {
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long val = numNormalAllocations() - numNormalDeallocations();
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return val >= 0 ? val : 0;
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}
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@Override
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public long numActiveHugeAllocations() {
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long val = numHugeAllocations() - numHugeDeallocations();
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return val >= 0 ? val : 0;
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}
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protected abstract PoolChunk<T> newChunk(int pageSize, int maxOrder, int pageShifts, int chunkSize);
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protected abstract PoolChunk<T> newUnpooledChunk(int capacity);
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protected abstract PooledByteBuf<T> newByteBuf(int maxCapacity);
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protected abstract void memoryCopy(T src, int srcOffset, T dst, int dstOffset, int length);
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protected abstract void destroyChunk(PoolChunk<T> chunk);
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@Override
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public synchronized String toString() {
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StringBuilder buf = new StringBuilder()
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.append("Chunk(s) at 0~25%:")
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130
buffer/src/main/java/io/netty/buffer/PoolArenaMetric.java
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130
buffer/src/main/java/io/netty/buffer/PoolArenaMetric.java
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@ -0,0 +1,130 @@
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/*
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* Copyright 2015 The Netty Project
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*
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* The Netty Project licenses this file to you under the Apache License,
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* version 2.0 (the "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*/
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package io.netty.buffer;
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import java.util.List;
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/**
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* Expose metrics for an arena.
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*/
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public interface PoolArenaMetric {
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/**
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* Returns the number of tiny sub-pages for the arena.
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*/
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int numTinySubpages();
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/**
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* Returns the number of small sub-pages for the arena.
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*/
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int numSmallSubpages();
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/**
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* Returns the number of chunk lists for the arena.
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*/
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int numChunkLists();
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/**
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* Returns an unmodifiable {@link List} which holds {@link PoolSubpageMetric}s for tiny sub-pages.
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*/
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List<PoolSubpageMetric> tinySubpages();
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/**
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* Returns an unmodifiable {@link List} which holds {@link PoolSubpageMetric}s for small sub-pages.
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*/
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List<PoolSubpageMetric> smallSubpages();
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/**
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* Returns an unmodifiable {@link List} which holds {@link PoolChunkListMetric}s.
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*/
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List<PoolChunkListMetric> chunkLists();
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/**
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* Return the number of allocations done via the arena. This includes all sizes.
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*/
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long numAllocations();
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/**
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* Return the number of tiny allocations done via the arena.
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*/
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long numTinyAllocations();
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/**
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* Return the number of small allocations done via the arena.
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*/
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long numSmallAllocations();
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/**
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* Return the number of normal allocations done via the arena.
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*/
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long numNormalAllocations();
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/**
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* Return the number of huge allocations done via the arena.
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*/
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long numHugeAllocations();
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/**
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* Return the number of deallocations done via the arena. This includes all sizes.
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*/
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long numDeallocations();
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/**
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* Return the number of tiny deallocations done via the arena.
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*/
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long numTinyDeallocations();
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/**
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* Return the number of small deallocations done via the arena.
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*/
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long numSmallDeallocations();
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/**
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* Return the number of normal deallocations done via the arena.
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*/
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long numNormalDeallocations();
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/**
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* Return the number of huge deallocations done via the arena.
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*/
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long numHugeDeallocations();
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/**
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* Return the number of currently active allocations.
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*/
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long numActiveAllocations();
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/**
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* Return the number of currently active tiny allocations.
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*/
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long numActiveTinyAllocations();
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/**
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* Return the number of currently active small allocations.
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*/
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long numActiveSmallAllocations();
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/**
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* Return the number of currently active normal allocations.
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*/
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long numActiveNormalAllocations();
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/**
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* Return the number of currently active huge allocations.
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*/
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long numActiveHugeAllocations();
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}
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@ -100,8 +100,7 @@ package io.netty.buffer;
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* where as per convention defined above
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* the second value (i.e, x) indicates that the first node which is free to be allocated is at depth x (from root)
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*/
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final class PoolChunk<T> {
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final class PoolChunk<T> implements PoolChunkMetric {
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final PoolArena<T> arena;
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final T memory;
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@ -186,7 +185,8 @@ final class PoolChunk<T> {
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return new PoolSubpage[size];
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}
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int usage() {
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@Override
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public int usage() {
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final int freeBytes = this.freeBytes;
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if (freeBytes == 0) {
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return 100;
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@ -414,6 +414,16 @@ final class PoolChunk<T> {
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return memoryMapIdx ^ maxSubpageAllocs; // remove highest set bit, to get offset
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}
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@Override
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public int chunkSize() {
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return chunkSize;
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}
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@Override
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public int freeBytes() {
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return freeBytes;
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}
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@Override
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public String toString() {
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return new StringBuilder()
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@ -18,7 +18,13 @@ package io.netty.buffer;
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import io.netty.util.internal.StringUtil;
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final class PoolChunkList<T> {
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import java.util.ArrayList;
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import java.util.Collections;
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import java.util.Iterator;
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import java.util.List;
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final class PoolChunkList<T> implements PoolChunkListMetric {
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private static final Iterator<PoolChunkMetric> EMPTY_METRICS = Collections.<PoolChunkMetric>emptyList().iterator();
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private final PoolArena<T> arena;
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private final PoolChunkList<T> nextList;
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PoolChunkList<T> prevList;
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@ -108,6 +114,32 @@ final class PoolChunkList<T> {
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}
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}
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@Override
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public int minUsage() {
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return minUsage;
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}
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@Override
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public int maxUsage() {
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return maxUsage;
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}
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@Override
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public Iterator<PoolChunkMetric> iterator() {
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if (head == null) {
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return EMPTY_METRICS;
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}
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List<PoolChunkMetric> metrics = new ArrayList<PoolChunkMetric>();
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for (PoolChunk<T> cur = head;;) {
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metrics.add(cur);
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cur = cur.next;
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if (cur == null) {
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break;
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}
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}
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return metrics.iterator();
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}
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@Override
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public String toString() {
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if (head == null) {
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@ -0,0 +1,32 @@
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/*
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* Copyright 2015 The Netty Project
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*
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* The Netty Project licenses this file to you under the Apache License,
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* version 2.0 (the "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
|
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
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* License for the specific language governing permissions and limitations
|
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* under the License.
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*/
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package io.netty.buffer;
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/**
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* Metrics for a list of chunks.
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*/
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public interface PoolChunkListMetric extends Iterable<PoolChunkMetric> {
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/**
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* Return the minum usage of the chunk list before which chunks are promoted to the previous list.
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*/
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int minUsage();
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/**
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* Return the minum usage of the chunk list after which chunks are promoted to the next list.
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*/
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int maxUsage();
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}
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37
buffer/src/main/java/io/netty/buffer/PoolChunkMetric.java
Normal file
37
buffer/src/main/java/io/netty/buffer/PoolChunkMetric.java
Normal file
@ -0,0 +1,37 @@
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/*
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* Copyright 2015 The Netty Project
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*
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* The Netty Project licenses this file to you under the Apache License,
|
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* version 2.0 (the "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* 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;
|
||||
|
||||
/**
|
||||
* Metrics for a chunk.
|
||||
*/
|
||||
public interface PoolChunkMetric {
|
||||
|
||||
/**
|
||||
* Return the percentage of the current usage of the chunk.
|
||||
*/
|
||||
int usage();
|
||||
|
||||
/**
|
||||
* Return the size of the chunk in bytes, this is the maximum of bytes that can be served out of the chunk.
|
||||
*/
|
||||
int chunkSize();
|
||||
|
||||
/**
|
||||
* Return the number of free bytes in the chunk.
|
||||
*/
|
||||
int freeBytes();
|
||||
}
|
||||
@ -16,7 +16,7 @@
|
||||
|
||||
package io.netty.buffer;
|
||||
|
||||
final class PoolSubpage<T> {
|
||||
final class PoolSubpage<T> implements PoolSubpageMetric {
|
||||
|
||||
final PoolChunk<T> chunk;
|
||||
private final int memoryMapIdx;
|
||||
@ -202,6 +202,7 @@ final class PoolSubpage<T> {
|
||||
return 0x4000000000000000L | (long) bitmapIdx << 32 | memoryMapIdx;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
if (!doNotDestroy) {
|
||||
return "(" + memoryMapIdx + ": not in use)";
|
||||
@ -210,4 +211,24 @@ final class PoolSubpage<T> {
|
||||
return String.valueOf('(') + memoryMapIdx + ": " + (maxNumElems - numAvail) + '/' + maxNumElems +
|
||||
", offset: " + runOffset + ", length: " + pageSize + ", elemSize: " + elemSize + ')';
|
||||
}
|
||||
|
||||
@Override
|
||||
public int maxNumElements() {
|
||||
return maxNumElems;
|
||||
}
|
||||
|
||||
@Override
|
||||
public int numAvailable() {
|
||||
return numAvail;
|
||||
}
|
||||
|
||||
@Override
|
||||
public int elementSize() {
|
||||
return elemSize;
|
||||
}
|
||||
|
||||
@Override
|
||||
public int pageSize() {
|
||||
return pageSize;
|
||||
}
|
||||
}
|
||||
|
||||
43
buffer/src/main/java/io/netty/buffer/PoolSubpageMetric.java
Normal file
43
buffer/src/main/java/io/netty/buffer/PoolSubpageMetric.java
Normal file
@ -0,0 +1,43 @@
|
||||
/*
|
||||
* Copyright 2015 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;
|
||||
|
||||
/**
|
||||
* Metrics for a sub-page.
|
||||
*/
|
||||
public interface PoolSubpageMetric {
|
||||
|
||||
/**
|
||||
* Return the number of maximal elements that can be allocated out of the sub-page.
|
||||
*/
|
||||
int maxNumElements();
|
||||
|
||||
/**
|
||||
* Return the number of available elements to be allocated.
|
||||
*/
|
||||
int numAvailable();
|
||||
|
||||
/**
|
||||
* Return the size (in bytes) of the elements that will be allocated.
|
||||
*/
|
||||
int elementSize();
|
||||
|
||||
/**
|
||||
* Return the size (in bytes) of this page.
|
||||
*/
|
||||
int pageSize();
|
||||
}
|
||||
|
||||
@ -23,6 +23,9 @@ 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.Collections;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicInteger;
|
||||
|
||||
public class PooledByteBufAllocator extends AbstractByteBufAllocator {
|
||||
@ -125,6 +128,9 @@ public class PooledByteBufAllocator extends AbstractByteBufAllocator {
|
||||
private final int smallCacheSize;
|
||||
private final int normalCacheSize;
|
||||
|
||||
private final List<PoolArenaMetric> heapArenaMetrics;
|
||||
private final List<PoolArenaMetric> directArenaMetrics;
|
||||
|
||||
final PoolThreadLocalCache threadCache;
|
||||
|
||||
public PooledByteBufAllocator() {
|
||||
@ -164,20 +170,31 @@ public class PooledByteBufAllocator extends AbstractByteBufAllocator {
|
||||
|
||||
if (nHeapArena > 0) {
|
||||
heapArenas = newArenaArray(nHeapArena);
|
||||
List<PoolArenaMetric> metrics = new ArrayList<PoolArenaMetric>(heapArenas.length);
|
||||
for (int i = 0; i < heapArenas.length; i ++) {
|
||||
heapArenas[i] = new PoolArena.HeapArena(this, pageSize, maxOrder, pageShifts, chunkSize);
|
||||
PoolArena.HeapArena arena = new PoolArena.HeapArena(this, pageSize, maxOrder, pageShifts, chunkSize);
|
||||
heapArenas[i] = arena;
|
||||
metrics.add(arena);
|
||||
}
|
||||
heapArenaMetrics = Collections.unmodifiableList(metrics);
|
||||
} else {
|
||||
heapArenas = null;
|
||||
heapArenaMetrics = Collections.emptyList();
|
||||
}
|
||||
|
||||
if (nDirectArena > 0) {
|
||||
directArenas = newArenaArray(nDirectArena);
|
||||
List<PoolArenaMetric> metrics = new ArrayList<PoolArenaMetric>(directArenas.length);
|
||||
for (int i = 0; i < directArenas.length; i ++) {
|
||||
directArenas[i] = new PoolArena.DirectArena(this, pageSize, maxOrder, pageShifts, chunkSize);
|
||||
PoolArena.DirectArena arena = new PoolArena.DirectArena(
|
||||
this, pageSize, maxOrder, pageShifts, chunkSize);
|
||||
directArenas[i] = arena;
|
||||
metrics.add(arena);
|
||||
}
|
||||
directArenaMetrics = Collections.unmodifiableList(metrics);
|
||||
} else {
|
||||
directArenas = null;
|
||||
directArenaMetrics = Collections.emptyList();
|
||||
}
|
||||
}
|
||||
|
||||
@ -283,9 +300,11 @@ public class PooledByteBufAllocator extends AbstractByteBufAllocator {
|
||||
|
||||
final class PoolThreadLocalCache extends FastThreadLocal<PoolThreadCache> {
|
||||
private final AtomicInteger index = new AtomicInteger();
|
||||
final AtomicInteger caches = new AtomicInteger();
|
||||
|
||||
@Override
|
||||
protected PoolThreadCache initialValue() {
|
||||
caches.incrementAndGet();
|
||||
final int idx = index.getAndIncrement();
|
||||
final PoolArena<byte[]> heapArena;
|
||||
final PoolArena<ByteBuffer> directArena;
|
||||
@ -301,7 +320,6 @@ public class PooledByteBufAllocator extends AbstractByteBufAllocator {
|
||||
} else {
|
||||
directArena = null;
|
||||
}
|
||||
|
||||
return new PoolThreadCache(
|
||||
heapArena, directArena, tinyCacheSize, smallCacheSize, normalCacheSize,
|
||||
DEFAULT_MAX_CACHED_BUFFER_CAPACITY, DEFAULT_CACHE_TRIM_INTERVAL);
|
||||
@ -310,25 +328,91 @@ public class PooledByteBufAllocator extends AbstractByteBufAllocator {
|
||||
@Override
|
||||
protected void onRemoval(PoolThreadCache value) {
|
||||
value.free();
|
||||
caches.decrementAndGet();
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the number of heap arenas.
|
||||
*/
|
||||
public int numHeapArenas() {
|
||||
return heapArenaMetrics.size();
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the number of direct arenas.
|
||||
*/
|
||||
public int numDirectArenas() {
|
||||
return directArenaMetrics.size();
|
||||
}
|
||||
|
||||
/**
|
||||
* Return a {@link List} of all heap {@link PoolArenaMetric}s that are provided by this pool.
|
||||
*/
|
||||
public List<PoolArenaMetric> heapArenas() {
|
||||
return heapArenaMetrics;
|
||||
}
|
||||
|
||||
/**
|
||||
* Return a {@link List} of all direct {@link PoolArenaMetric}s that are provided by this pool.
|
||||
*/
|
||||
public List<PoolArenaMetric> directArenas() {
|
||||
return directArenaMetrics;
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the number of thread local caches used by this {@link PooledByteBufAllocator}.
|
||||
*/
|
||||
public int numThreadLocalCaches() {
|
||||
return threadCache.caches.get();
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the size of the tiny cache.
|
||||
*/
|
||||
public int tinyCacheSize() {
|
||||
return tinyCacheSize;
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the size of the small cache.
|
||||
*/
|
||||
public int smallCacheSize() {
|
||||
return smallCacheSize;
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the size of the normal cache.
|
||||
*/
|
||||
public int normalCacheSize() {
|
||||
return normalCacheSize;
|
||||
}
|
||||
|
||||
// Too noisy at the moment.
|
||||
//
|
||||
//public String toString() {
|
||||
// StringBuilder buf = new StringBuilder();
|
||||
// buf.append(heapArenas.length);
|
||||
// int heapArenasLen = heapArenas == null ? 0 : heapArenas.length;
|
||||
// buf.append(heapArenasLen);
|
||||
// buf.append(" heap arena(s):");
|
||||
// buf.append(StringUtil.NEWLINE);
|
||||
// if (heapArenasLen > 0) {
|
||||
// for (PoolArena<byte[]> a: heapArenas) {
|
||||
// buf.append(a);
|
||||
// }
|
||||
// buf.append(directArenas.length);
|
||||
// }
|
||||
//
|
||||
// int directArenasLen = directArenas == null ? 0 : directArenas.length;
|
||||
//
|
||||
// buf.append(directArenasLen);
|
||||
// buf.append(" direct arena(s):");
|
||||
// buf.append(StringUtil.NEWLINE);
|
||||
// if (directArenasLen > 0) {
|
||||
// for (PoolArena<ByteBuffer> a: directArenas) {
|
||||
// buf.append(a);
|
||||
// }
|
||||
// }
|
||||
//
|
||||
// return buf.toString();
|
||||
//}
|
||||
}
|
||||
|
||||
26
common/src/main/java/io/netty/util/internal/LongCounter.java
Normal file
26
common/src/main/java/io/netty/util/internal/LongCounter.java
Normal file
@ -0,0 +1,26 @@
|
||||
/*
|
||||
* Copyright 2015 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.util.internal;
|
||||
|
||||
/**
|
||||
* Counter for long.
|
||||
*/
|
||||
public interface LongCounter {
|
||||
void add(long delta);
|
||||
void increment();
|
||||
void decrement();
|
||||
long value();
|
||||
}
|
||||
@ -17,6 +17,7 @@ package io.netty.util.internal;
|
||||
|
||||
import io.netty.util.CharsetUtil;
|
||||
import io.netty.util.internal.chmv8.ConcurrentHashMapV8;
|
||||
import io.netty.util.internal.chmv8.LongAdderV8;
|
||||
import io.netty.util.internal.logging.InternalLogger;
|
||||
import io.netty.util.internal.logging.InternalLoggerFactory;
|
||||
|
||||
@ -40,6 +41,7 @@ import java.util.concurrent.ConcurrentLinkedDeque;
|
||||
import java.util.concurrent.ConcurrentMap;
|
||||
import java.util.concurrent.LinkedBlockingDeque;
|
||||
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
|
||||
import java.util.concurrent.atomic.AtomicLong;
|
||||
import java.util.concurrent.atomic.AtomicLongFieldUpdater;
|
||||
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
|
||||
import java.util.regex.Matcher;
|
||||
@ -228,6 +230,17 @@ public final class PlatformDependent {
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a new fastest {@link LongCounter} implementaion for the current platform.
|
||||
*/
|
||||
public static LongCounter newLongCounter() {
|
||||
if (HAS_UNSAFE) {
|
||||
return new LongAdderV8();
|
||||
} else {
|
||||
return new AtomicLongCounter();
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a new fastest {@link ConcurrentMap} implementaion for the current platform.
|
||||
*/
|
||||
@ -861,6 +874,28 @@ public final class PlatformDependent {
|
||||
return PlatformDependent0.addressSize();
|
||||
}
|
||||
|
||||
private static final class AtomicLongCounter extends AtomicLong implements LongCounter {
|
||||
@Override
|
||||
public void add(long delta) {
|
||||
addAndGet(delta);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void increment() {
|
||||
incrementAndGet();
|
||||
}
|
||||
|
||||
@Override
|
||||
public void decrement() {
|
||||
decrementAndGet();
|
||||
}
|
||||
|
||||
@Override
|
||||
public long value() {
|
||||
return get();
|
||||
}
|
||||
}
|
||||
|
||||
private PlatformDependent() {
|
||||
// only static method supported
|
||||
}
|
||||
|
||||
@ -0,0 +1,225 @@
|
||||
/*
|
||||
* Copyright 2015 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.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Written by Doug Lea with assistance from members of JCP JSR-166
|
||||
* Expert Group and released to the public domain, as explained at
|
||||
* http://creativecommons.org/publicdomain/zero/1.0/
|
||||
*/
|
||||
package io.netty.util.internal.chmv8;
|
||||
|
||||
|
||||
import io.netty.util.internal.LongCounter;
|
||||
|
||||
import java.io.IOException;
|
||||
import java.io.ObjectInputStream;
|
||||
import java.io.ObjectOutputStream;
|
||||
import java.io.Serializable;
|
||||
import java.util.concurrent.atomic.AtomicLong;
|
||||
|
||||
/**
|
||||
* One or more variables that together maintain an initially zero
|
||||
* {@code long} sum. When updates (method {@link #add}) are contended
|
||||
* across threads, the set of variables may grow dynamically to reduce
|
||||
* contention. Method {@link #sum} (or, equivalently, {@link
|
||||
* #longValue}) returns the current total combined across the
|
||||
* variables maintaining the sum.
|
||||
*
|
||||
* <p>This class is usually preferable to {@link AtomicLong} when
|
||||
* multiple threads update a common sum that is used for purposes such
|
||||
* as collecting statistics, not for fine-grained synchronization
|
||||
* control. Under low update contention, the two classes have similar
|
||||
* characteristics. But under high contention, expected throughput of
|
||||
* this class is significantly higher, at the expense of higher space
|
||||
* consumption.
|
||||
*
|
||||
* <p>This class extends {@link Number}, but does <em>not</em> define
|
||||
* methods such as {@code equals}, {@code hashCode} and {@code
|
||||
* compareTo} because instances are expected to be mutated, and so are
|
||||
* not useful as collection keys.
|
||||
*
|
||||
* <p><em>jsr166e note: This class is targeted to be placed in
|
||||
* java.util.concurrent.atomic.</em>
|
||||
*
|
||||
* @since 1.8
|
||||
* @author Doug Lea
|
||||
*/
|
||||
@SuppressWarnings("all")
|
||||
public class LongAdderV8 extends Striped64 implements Serializable, LongCounter {
|
||||
private static final long serialVersionUID = 7249069246863182397L;
|
||||
|
||||
/**
|
||||
* Version of plus for use in retryUpdate
|
||||
*/
|
||||
final long fn(long v, long x) { return v + x; }
|
||||
|
||||
/**
|
||||
* Creates a new adder with initial sum of zero.
|
||||
*/
|
||||
public LongAdderV8() {
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds the given value.
|
||||
*
|
||||
* @param x the value to add
|
||||
*/
|
||||
public void add(long x) {
|
||||
Cell[] as; long b, v; int[] hc; Cell a; int n;
|
||||
if ((as = cells) != null || !casBase(b = base, b + x)) {
|
||||
boolean uncontended = true;
|
||||
if ((hc = threadHashCode.get()) == null ||
|
||||
as == null || (n = as.length) < 1 ||
|
||||
(a = as[(n - 1) & hc[0]]) == null ||
|
||||
!(uncontended = a.cas(v = a.value, v + x)))
|
||||
retryUpdate(x, hc, uncontended);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Equivalent to {@code add(1)}.
|
||||
*/
|
||||
public void increment() {
|
||||
add(1L);
|
||||
}
|
||||
|
||||
/**
|
||||
* Equivalent to {@code add(-1)}.
|
||||
*/
|
||||
public void decrement() {
|
||||
add(-1L);
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the current sum. The returned value is <em>NOT</em> an
|
||||
* atomic snapshot; invocation in the absence of concurrent
|
||||
* updates returns an accurate result, but concurrent updates that
|
||||
* occur while the sum is being calculated might not be
|
||||
* incorporated.
|
||||
*
|
||||
* @return the sum
|
||||
*/
|
||||
public long sum() {
|
||||
long sum = base;
|
||||
Cell[] as = cells;
|
||||
if (as != null) {
|
||||
int n = as.length;
|
||||
for (int i = 0; i < n; ++i) {
|
||||
Cell a = as[i];
|
||||
if (a != null)
|
||||
sum += a.value;
|
||||
}
|
||||
}
|
||||
return sum;
|
||||
}
|
||||
|
||||
/**
|
||||
* Resets variables maintaining the sum to zero. This method may
|
||||
* be a useful alternative to creating a new adder, but is only
|
||||
* effective if there are no concurrent updates. Because this
|
||||
* method is intrinsically racy, it should only be used when it is
|
||||
* known that no threads are concurrently updating.
|
||||
*/
|
||||
public void reset() {
|
||||
internalReset(0L);
|
||||
}
|
||||
|
||||
/**
|
||||
* Equivalent in effect to {@link #sum} followed by {@link
|
||||
* #reset}. This method may apply for example during quiescent
|
||||
* points between multithreaded computations. If there are
|
||||
* updates concurrent with this method, the returned value is
|
||||
* <em>not</em> guaranteed to be the final value occurring before
|
||||
* the reset.
|
||||
*
|
||||
* @return the sum
|
||||
*/
|
||||
public long sumThenReset() {
|
||||
long sum = base;
|
||||
Cell[] as = cells;
|
||||
base = 0L;
|
||||
if (as != null) {
|
||||
int n = as.length;
|
||||
for (int i = 0; i < n; ++i) {
|
||||
Cell a = as[i];
|
||||
if (a != null) {
|
||||
sum += a.value;
|
||||
a.value = 0L;
|
||||
}
|
||||
}
|
||||
}
|
||||
return sum;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the String representation of the {@link #sum}.
|
||||
* @return the String representation of the {@link #sum}
|
||||
*/
|
||||
public String toString() {
|
||||
return Long.toString(sum());
|
||||
}
|
||||
|
||||
/**
|
||||
* Equivalent to {@link #sum}.
|
||||
*
|
||||
* @return the sum
|
||||
*/
|
||||
public long longValue() {
|
||||
return sum();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the {@link #sum} as an {@code int} after a narrowing
|
||||
* primitive conversion.
|
||||
*/
|
||||
public int intValue() {
|
||||
return (int)sum();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the {@link #sum} as a {@code float}
|
||||
* after a widening primitive conversion.
|
||||
*/
|
||||
public float floatValue() {
|
||||
return (float)sum();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the {@link #sum} as a {@code double} after a widening
|
||||
* primitive conversion.
|
||||
*/
|
||||
public double doubleValue() {
|
||||
return (double)sum();
|
||||
}
|
||||
|
||||
private void writeObject(ObjectOutputStream s) throws IOException {
|
||||
s.defaultWriteObject();
|
||||
s.writeLong(sum());
|
||||
}
|
||||
|
||||
private void readObject(ObjectInputStream s)
|
||||
throws IOException, ClassNotFoundException {
|
||||
s.defaultReadObject();
|
||||
busy = 0;
|
||||
cells = null;
|
||||
base = s.readLong();
|
||||
}
|
||||
|
||||
@Override
|
||||
public long value() {
|
||||
return sum();
|
||||
}
|
||||
}
|
||||
351
common/src/main/java/io/netty/util/internal/chmv8/Striped64.java
Normal file
351
common/src/main/java/io/netty/util/internal/chmv8/Striped64.java
Normal file
@ -0,0 +1,351 @@
|
||||
/*
|
||||
* Copyright 2015 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.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Written by Doug Lea with assistance from members of JCP JSR-166
|
||||
* Expert Group and released to the public domain, as explained at
|
||||
* http://creativecommons.org/publicdomain/zero/1.0/
|
||||
*/
|
||||
package io.netty.util.internal.chmv8;
|
||||
|
||||
|
||||
import java.util.Random;
|
||||
|
||||
/**
|
||||
* A package-local class holding common representation and mechanics
|
||||
* for classes supporting dynamic striping on 64bit values. The class
|
||||
* extends Number so that concrete subclasses must publicly do so.
|
||||
*/
|
||||
@SuppressWarnings("all")
|
||||
abstract class Striped64 extends Number {
|
||||
/*
|
||||
* This class maintains a lazily-initialized table of atomically
|
||||
* updated variables, plus an extra "base" field. The table size
|
||||
* is a power of two. Indexing uses masked per-thread hash codes.
|
||||
* Nearly all declarations in this class are package-private,
|
||||
* accessed directly by subclasses.
|
||||
*
|
||||
* Table entries are of class Cell; a variant of AtomicLong padded
|
||||
* to reduce cache contention on most processors. Padding is
|
||||
* overkill for most Atomics because they are usually irregularly
|
||||
* scattered in memory and thus don't interfere much with each
|
||||
* other. But Atomic objects residing in arrays will tend to be
|
||||
* placed adjacent to each other, and so will most often share
|
||||
* cache lines (with a huge negative performance impact) without
|
||||
* this precaution.
|
||||
*
|
||||
* In part because Cells are relatively large, we avoid creating
|
||||
* them until they are needed. When there is no contention, all
|
||||
* updates are made to the base field. Upon first contention (a
|
||||
* failed CAS on base update), the table is initialized to size 2.
|
||||
* The table size is doubled upon further contention until
|
||||
* reaching the nearest power of two greater than or equal to the
|
||||
* number of CPUS. Table slots remain empty (null) until they are
|
||||
* needed.
|
||||
*
|
||||
* A single spinlock ("busy") is used for initializing and
|
||||
* resizing the table, as well as populating slots with new Cells.
|
||||
* There is no need for a blocking lock; when the lock is not
|
||||
* available, threads try other slots (or the base). During these
|
||||
* retries, there is increased contention and reduced locality,
|
||||
* which is still better than alternatives.
|
||||
*
|
||||
* Per-thread hash codes are initialized to random values.
|
||||
* Contention and/or table collisions are indicated by failed
|
||||
* CASes when performing an update operation (see method
|
||||
* retryUpdate). Upon a collision, if the table size is less than
|
||||
* the capacity, it is doubled in size unless some other thread
|
||||
* holds the lock. If a hashed slot is empty, and lock is
|
||||
* available, a new Cell is created. Otherwise, if the slot
|
||||
* exists, a CAS is tried. Retries proceed by "double hashing",
|
||||
* using a secondary hash (Marsaglia XorShift) to try to find a
|
||||
* free slot.
|
||||
*
|
||||
* The table size is capped because, when there are more threads
|
||||
* than CPUs, supposing that each thread were bound to a CPU,
|
||||
* there would exist a perfect hash function mapping threads to
|
||||
* slots that eliminates collisions. When we reach capacity, we
|
||||
* search for this mapping by randomly varying the hash codes of
|
||||
* colliding threads. Because search is random, and collisions
|
||||
* only become known via CAS failures, convergence can be slow,
|
||||
* and because threads are typically not bound to CPUS forever,
|
||||
* may not occur at all. However, despite these limitations,
|
||||
* observed contention rates are typically low in these cases.
|
||||
*
|
||||
* It is possible for a Cell to become unused when threads that
|
||||
* once hashed to it terminate, as well as in the case where
|
||||
* doubling the table causes no thread to hash to it under
|
||||
* expanded mask. We do not try to detect or remove such cells,
|
||||
* under the assumption that for long-running instances, observed
|
||||
* contention levels will recur, so the cells will eventually be
|
||||
* needed again; and for short-lived ones, it does not matter.
|
||||
*/
|
||||
|
||||
/**
|
||||
* Padded variant of AtomicLong supporting only raw accesses plus CAS.
|
||||
* The value field is placed between pads, hoping that the JVM doesn't
|
||||
* reorder them.
|
||||
*
|
||||
* JVM intrinsics note: It would be possible to use a release-only
|
||||
* form of CAS here, if it were provided.
|
||||
*/
|
||||
static final class Cell {
|
||||
volatile long p0, p1, p2, p3, p4, p5, p6;
|
||||
volatile long value;
|
||||
volatile long q0, q1, q2, q3, q4, q5, q6;
|
||||
Cell(long x) { value = x; }
|
||||
|
||||
final boolean cas(long cmp, long val) {
|
||||
return UNSAFE.compareAndSwapLong(this, valueOffset, cmp, val);
|
||||
}
|
||||
|
||||
// Unsafe mechanics
|
||||
private static final sun.misc.Unsafe UNSAFE;
|
||||
private static final long valueOffset;
|
||||
static {
|
||||
try {
|
||||
UNSAFE = getUnsafe();
|
||||
Class<?> ak = Cell.class;
|
||||
valueOffset = UNSAFE.objectFieldOffset
|
||||
(ak.getDeclaredField("value"));
|
||||
} catch (Exception e) {
|
||||
throw new Error(e);
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* ThreadLocal holding a single-slot int array holding hash code.
|
||||
* Unlike the JDK8 version of this class, we use a suboptimal
|
||||
* int[] representation to avoid introducing a new type that can
|
||||
* impede class-unloading when ThreadLocals are not removed.
|
||||
*/
|
||||
static final ThreadLocal<int[]> threadHashCode = new ThreadLocal<int[]>();
|
||||
|
||||
/**
|
||||
* Generator of new random hash codes
|
||||
*/
|
||||
static final Random rng = new Random();
|
||||
|
||||
/** Number of CPUS, to place bound on table size */
|
||||
static final int NCPU = Runtime.getRuntime().availableProcessors();
|
||||
|
||||
/**
|
||||
* Table of cells. When non-null, size is a power of 2.
|
||||
*/
|
||||
transient volatile Cell[] cells;
|
||||
|
||||
/**
|
||||
* Base value, used mainly when there is no contention, but also as
|
||||
* a fallback during table initialization races. Updated via CAS.
|
||||
*/
|
||||
transient volatile long base;
|
||||
|
||||
/**
|
||||
* Spinlock (locked via CAS) used when resizing and/or creating Cells.
|
||||
*/
|
||||
transient volatile int busy;
|
||||
|
||||
/**
|
||||
* Package-private default constructor
|
||||
*/
|
||||
Striped64() {
|
||||
}
|
||||
|
||||
/**
|
||||
* CASes the base field.
|
||||
*/
|
||||
final boolean casBase(long cmp, long val) {
|
||||
return UNSAFE.compareAndSwapLong(this, baseOffset, cmp, val);
|
||||
}
|
||||
|
||||
/**
|
||||
* CASes the busy field from 0 to 1 to acquire lock.
|
||||
*/
|
||||
final boolean casBusy() {
|
||||
return UNSAFE.compareAndSwapInt(this, busyOffset, 0, 1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Computes the function of current and new value. Subclasses
|
||||
* should open-code this update function for most uses, but the
|
||||
* virtualized form is needed within retryUpdate.
|
||||
*
|
||||
* @param currentValue the current value (of either base or a cell)
|
||||
* @param newValue the argument from a user update call
|
||||
* @return result of the update function
|
||||
*/
|
||||
abstract long fn(long currentValue, long newValue);
|
||||
|
||||
/**
|
||||
* Handles cases of updates involving initialization, resizing,
|
||||
* creating new Cells, and/or contention. See above for
|
||||
* explanation. This method suffers the usual non-modularity
|
||||
* problems of optimistic retry code, relying on rechecked sets of
|
||||
* reads.
|
||||
*
|
||||
* @param x the value
|
||||
* @param hc the hash code holder
|
||||
* @param wasUncontended false if CAS failed before call
|
||||
*/
|
||||
final void retryUpdate(long x, int[] hc, boolean wasUncontended) {
|
||||
int h;
|
||||
if (hc == null) {
|
||||
threadHashCode.set(hc = new int[1]); // Initialize randomly
|
||||
int r = rng.nextInt(); // Avoid zero to allow xorShift rehash
|
||||
h = hc[0] = (r == 0) ? 1 : r;
|
||||
}
|
||||
else
|
||||
h = hc[0];
|
||||
boolean collide = false; // True if last slot nonempty
|
||||
for (;;) {
|
||||
Cell[] as; Cell a; int n; long v;
|
||||
if ((as = cells) != null && (n = as.length) > 0) {
|
||||
if ((a = as[(n - 1) & h]) == null) {
|
||||
if (busy == 0) { // Try to attach new Cell
|
||||
Cell r = new Cell(x); // Optimistically create
|
||||
if (busy == 0 && casBusy()) {
|
||||
boolean created = false;
|
||||
try { // Recheck under lock
|
||||
Cell[] rs; int m, j;
|
||||
if ((rs = cells) != null &&
|
||||
(m = rs.length) > 0 &&
|
||||
rs[j = (m - 1) & h] == null) {
|
||||
rs[j] = r;
|
||||
created = true;
|
||||
}
|
||||
} finally {
|
||||
busy = 0;
|
||||
}
|
||||
if (created)
|
||||
break;
|
||||
continue; // Slot is now non-empty
|
||||
}
|
||||
}
|
||||
collide = false;
|
||||
}
|
||||
else if (!wasUncontended) // CAS already known to fail
|
||||
wasUncontended = true; // Continue after rehash
|
||||
else if (a.cas(v = a.value, fn(v, x)))
|
||||
break;
|
||||
else if (n >= NCPU || cells != as)
|
||||
collide = false; // At max size or stale
|
||||
else if (!collide)
|
||||
collide = true;
|
||||
else if (busy == 0 && casBusy()) {
|
||||
try {
|
||||
if (cells == as) { // Expand table unless stale
|
||||
Cell[] rs = new Cell[n << 1];
|
||||
for (int i = 0; i < n; ++i)
|
||||
rs[i] = as[i];
|
||||
cells = rs;
|
||||
}
|
||||
} finally {
|
||||
busy = 0;
|
||||
}
|
||||
collide = false;
|
||||
continue; // Retry with expanded table
|
||||
}
|
||||
h ^= h << 13; // Rehash
|
||||
h ^= h >>> 17;
|
||||
h ^= h << 5;
|
||||
hc[0] = h; // Record index for next time
|
||||
}
|
||||
else if (busy == 0 && cells == as && casBusy()) {
|
||||
boolean init = false;
|
||||
try { // Initialize table
|
||||
if (cells == as) {
|
||||
Cell[] rs = new Cell[2];
|
||||
rs[h & 1] = new Cell(x);
|
||||
cells = rs;
|
||||
init = true;
|
||||
}
|
||||
} finally {
|
||||
busy = 0;
|
||||
}
|
||||
if (init)
|
||||
break;
|
||||
}
|
||||
else if (casBase(v = base, fn(v, x)))
|
||||
break; // Fall back on using base
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Sets base and all cells to the given value.
|
||||
*/
|
||||
final void internalReset(long initialValue) {
|
||||
Cell[] as = cells;
|
||||
base = initialValue;
|
||||
if (as != null) {
|
||||
int n = as.length;
|
||||
for (int i = 0; i < n; ++i) {
|
||||
Cell a = as[i];
|
||||
if (a != null)
|
||||
a.value = initialValue;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Unsafe mechanics
|
||||
private static final sun.misc.Unsafe UNSAFE;
|
||||
private static final long baseOffset;
|
||||
private static final long busyOffset;
|
||||
static {
|
||||
try {
|
||||
UNSAFE = getUnsafe();
|
||||
Class<?> sk = Striped64.class;
|
||||
baseOffset = UNSAFE.objectFieldOffset
|
||||
(sk.getDeclaredField("base"));
|
||||
busyOffset = UNSAFE.objectFieldOffset
|
||||
(sk.getDeclaredField("busy"));
|
||||
} catch (Exception e) {
|
||||
throw new Error(e);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package.
|
||||
* Replace with a simple call to Unsafe.getUnsafe when integrating
|
||||
* into a jdk.
|
||||
*
|
||||
* @return a sun.misc.Unsafe
|
||||
*/
|
||||
private static sun.misc.Unsafe getUnsafe() {
|
||||
try {
|
||||
return sun.misc.Unsafe.getUnsafe();
|
||||
} catch (SecurityException tryReflectionInstead) {}
|
||||
try {
|
||||
return java.security.AccessController.doPrivileged
|
||||
(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() {
|
||||
public sun.misc.Unsafe run() throws Exception {
|
||||
Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
|
||||
for (java.lang.reflect.Field f : k.getDeclaredFields()) {
|
||||
f.setAccessible(true);
|
||||
Object x = f.get(null);
|
||||
if (k.isInstance(x))
|
||||
return k.cast(x);
|
||||
}
|
||||
throw new NoSuchFieldError("the Unsafe");
|
||||
}});
|
||||
} catch (java.security.PrivilegedActionException e) {
|
||||
throw new RuntimeException("Could not initialize intrinsics",
|
||||
e.getCause());
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user