[#5224] Allow to use Unsafe.reallocateMemory(...) in UnpooledUnsafeNoCleanerDirectByteBuf.

Motivation:

If the user uses unsafe direct buffers with no cleaner we can use Unsafe.reallocateMemory(...) as optimization when we need to expand the buffer.

Modifications:

Use Unsafe.relocateMemory(...) in UnpooledUnsafeNoCleanerDirectByteBuf.

Result:

Less expensive expanding of buffers.
This commit is contained in:
Norman Maurer 2016-05-23 13:56:21 +02:00
parent 9bd94ea021
commit 3a7dcde320
4 changed files with 97 additions and 31 deletions

View File

@ -37,10 +37,10 @@ public class UnpooledUnsafeDirectByteBuf extends AbstractReferenceCountedByteBuf
private final ByteBufAllocator alloc;
private long memoryAddress;
private ByteBuffer buffer;
private ByteBuffer tmpNioBuf;
private int capacity;
private boolean doNotFree;
ByteBuffer buffer;
/**
* Creates a new direct buffer.
@ -65,7 +65,7 @@ public class UnpooledUnsafeDirectByteBuf extends AbstractReferenceCountedByteBuf
}
this.alloc = alloc;
setByteBuffer(allocateDirect(initialCapacity));
setByteBuffer(allocateDirect(initialCapacity), false);
}
/**
@ -96,7 +96,7 @@ public class UnpooledUnsafeDirectByteBuf extends AbstractReferenceCountedByteBuf
this.alloc = alloc;
doNotFree = true;
setByteBuffer(initialBuffer.slice().order(ByteOrder.BIG_ENDIAN));
setByteBuffer(initialBuffer.slice().order(ByteOrder.BIG_ENDIAN), false);
writerIndex(initialCapacity);
}
@ -114,16 +114,17 @@ public class UnpooledUnsafeDirectByteBuf extends AbstractReferenceCountedByteBuf
PlatformDependent.freeDirectBuffer(buffer);
}
private void setByteBuffer(ByteBuffer buffer) {
ByteBuffer oldBuffer = this.buffer;
if (oldBuffer != null) {
if (doNotFree) {
doNotFree = false;
} else {
freeDirect(oldBuffer);
final void setByteBuffer(ByteBuffer buffer, boolean tryFree) {
if (tryFree) {
ByteBuffer oldBuffer = this.buffer;
if (oldBuffer != null) {
if (doNotFree) {
doNotFree = false;
} else {
freeDirect(oldBuffer);
}
}
}
this.buffer = buffer;
memoryAddress = PlatformDependent.directBufferAddress(buffer);
tmpNioBuf = null;
@ -158,7 +159,7 @@ public class UnpooledUnsafeDirectByteBuf extends AbstractReferenceCountedByteBuf
newBuffer.position(0).limit(oldBuffer.capacity());
newBuffer.put(oldBuffer);
newBuffer.clear();
setByteBuffer(newBuffer);
setByteBuffer(newBuffer, true);
} else if (newCapacity < oldCapacity) {
ByteBuffer oldBuffer = buffer;
ByteBuffer newBuffer = allocateDirect(newCapacity);
@ -173,7 +174,7 @@ public class UnpooledUnsafeDirectByteBuf extends AbstractReferenceCountedByteBuf
} else {
setIndex(newCapacity, newCapacity);
}
setByteBuffer(newBuffer);
setByteBuffer(newBuffer, true);
}
return this;
}

View File

@ -34,4 +34,39 @@ final class UnpooledUnsafeNoCleanerDirectByteBuf extends UnpooledUnsafeDirectByt
protected void freeDirect(ByteBuffer buffer) {
PlatformDependent.freeDirectNoCleaner(buffer);
}
@Override
public ByteBuf capacity(int newCapacity) {
ensureAccessible();
if (newCapacity < 0 || newCapacity > maxCapacity()) {
throw new IllegalArgumentException("newCapacity: " + newCapacity);
}
int readerIndex = readerIndex();
int writerIndex = writerIndex();
int oldCapacity = capacity();
if (newCapacity > oldCapacity) {
ByteBuffer oldBuffer = buffer;
ByteBuffer newBuffer = PlatformDependent.reallocateDirectNoCleaner(oldBuffer, newCapacity);
setByteBuffer(newBuffer, false);
} else if (newCapacity < oldCapacity) {
ByteBuffer oldBuffer = buffer;
ByteBuffer newBuffer = allocateDirect(newCapacity);
if (readerIndex < newCapacity) {
if (writerIndex > newCapacity) {
writerIndex = newCapacity;
writerIndex(writerIndex);
}
oldBuffer.position(readerIndex).limit(writerIndex);
newBuffer.position(readerIndex).limit(writerIndex);
newBuffer.put(oldBuffer);
newBuffer.clear();
} else {
setIndex(newCapacity, newCapacity);
}
setByteBuffer(newBuffer, true);
}
return this;
}
}

View File

@ -543,25 +543,29 @@ public final class PlatformDependent {
public static ByteBuffer allocateDirectNoCleaner(int capacity) {
assert USE_DIRECT_BUFFER_NO_CLEANER;
if (DIRECT_MEMORY_COUNTER != null) {
for (;;) {
long usedMemory = DIRECT_MEMORY_COUNTER.get();
long newUsedMemory = usedMemory + capacity;
if (newUsedMemory > DIRECT_MEMORY_LIMIT) {
throw new OutOfDirectMemoryError("failed to allocate " + capacity
+ " byte(s) of direct memory (used: " + usedMemory + ", max: " + DIRECT_MEMORY_LIMIT + ')');
}
if (DIRECT_MEMORY_COUNTER.compareAndSet(usedMemory, newUsedMemory)) {
break;
}
}
}
incrementMemoryCounter(capacity);
try {
return PlatformDependent0.allocateDirectNoCleaner(capacity);
} catch (Throwable e) {
if (DIRECT_MEMORY_COUNTER != null) {
DIRECT_MEMORY_COUNTER.addAndGet(-capacity);
}
decrementMemoryCounter(capacity);
throwException(e);
return null;
}
}
/**
* Reallocate a new {@link ByteBuffer} with the given {@code capacity}. {@link ByteBuffer}s reallocated with
* this method <strong>MUST</strong> be deallocated via {@link #freeDirectNoCleaner(ByteBuffer)}.
*/
public static ByteBuffer reallocateDirectNoCleaner(ByteBuffer buffer, int capacity) {
assert USE_DIRECT_BUFFER_NO_CLEANER;
int len = capacity - buffer.capacity();
incrementMemoryCounter(len);
try {
return PlatformDependent0.reallocateDirectNoCleaner(buffer, capacity);
} catch (Throwable e) {
decrementMemoryCounter(len);
throwException(e);
return null;
}
@ -576,6 +580,26 @@ public final class PlatformDependent {
int capacity = buffer.capacity();
PlatformDependent0.freeMemory(PlatformDependent0.directBufferAddress(buffer));
decrementMemoryCounter(capacity);
}
private static void incrementMemoryCounter(int capacity) {
if (DIRECT_MEMORY_COUNTER != null) {
for (;;) {
long usedMemory = DIRECT_MEMORY_COUNTER.get();
long newUsedMemory = usedMemory + capacity;
if (newUsedMemory > DIRECT_MEMORY_LIMIT) {
throw new OutOfDirectMemoryError("failed to allocate " + capacity
+ " byte(s) of direct memory (used: " + usedMemory + ", max: " + DIRECT_MEMORY_LIMIT + ')');
}
if (DIRECT_MEMORY_COUNTER.compareAndSet(usedMemory, newUsedMemory)) {
break;
}
}
}
}
private static void decrementMemoryCounter(int capacity) {
if (DIRECT_MEMORY_COUNTER != null) {
long usedMemory = DIRECT_MEMORY_COUNTER.addAndGet(-capacity);
assert usedMemory >= 0;

View File

@ -228,9 +228,15 @@ final class PlatformDependent0 {
return DIRECT_BUFFER_CONSTRUCTOR != null;
}
static ByteBuffer reallocateDirectNoCleaner(ByteBuffer buffer, int capacity) {
return newDirectBuffer(UNSAFE.reallocateMemory(directBufferAddress(buffer), capacity), capacity);
}
static ByteBuffer allocateDirectNoCleaner(int capacity) {
assert DIRECT_BUFFER_CONSTRUCTOR != null;
long address = UNSAFE.allocateMemory(capacity);
return newDirectBuffer(UNSAFE.allocateMemory(capacity), capacity);
}
private static ByteBuffer newDirectBuffer(long address, int capacity) {
try {
return (ByteBuffer) DIRECT_BUFFER_CONSTRUCTOR.newInstance(address, capacity);
} catch (Throwable cause) {