com.landawn.abacus.cache.OffHeapCache Maven / Gradle / Ivy
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/*
* Copyright (c) 2015, Haiyang Li. All rights reserved.
*/
package com.landawn.abacus.cache;
import java.io.ByteArrayInputStream;
import java.lang.reflect.Field;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.BitSet;
import java.util.Deque;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import com.landawn.abacus.exception.AbacusException;
import com.landawn.abacus.logging.Logger;
import com.landawn.abacus.logging.LoggerFactory;
import com.landawn.abacus.parser.Parser;
import com.landawn.abacus.parser.ParserFactory;
import com.landawn.abacus.pool.AbstractPoolable;
import com.landawn.abacus.pool.KeyedObjectPool;
import com.landawn.abacus.pool.PoolFactory;
import com.landawn.abacus.type.ByteBufferType;
import com.landawn.abacus.type.Type;
import com.landawn.abacus.type.TypeFactory;
import com.landawn.abacus.util.AsyncExecutor;
import com.landawn.abacus.util.ByteArrayOutputStream;
import com.landawn.abacus.util.IOUtil;
import com.landawn.abacus.util.MoreExecutors;
import com.landawn.abacus.util.N;
import com.landawn.abacus.util.Objectory;
import com.landawn.abacus.util.Try;
import sun.misc.Unsafe;
/**
* It's not designed for tiny objects(length of bytes < 128 after serialization).
* Since it's off heap cache, modifying the objects from cache won't impact the objects in cache.
*
* @param
* @param
*
* @since 0.8
*
* @author haiyang li
*/
public class OffHeapCache extends AbstractCache {
private static final Logger logger = LoggerFactory.getLogger(OffHeapCache.class);
// /**
// * Sets all bytes in a given block of memory to a copy of another
// * block.
// *
// * This method determines each block's base address by means of two parameters,
// * and so it provides (in effect) a double-register addressing mode,
// * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
// * the offset supplies an absolute base address.
// *
// *
The transfers are in coherent (atomic) units of a size determined
// * by the address and length parameters. If the effective addresses and
// * length are all even modulo 8, the transfer takes place in 'long' units.
// * If the effective addresses and length are (resp.) even modulo 4 or 2,
// * the transfer takes place in units of 'int' or 'short'.
// *
// * @since 1.7
// */
// public native void copyMemory(Object srcBase, long srcOffset,
// Object destBase, long destOffset,
// long bytes);
private static final Parser parser = ParserFactory.isKryoAvailable() ? ParserFactory.createKryoParser() : ParserFactory.createJSONParser();
private static final ByteBufferType bbType = (ByteBufferType) ((Type) TypeFactory.getType(ByteBufferType.BYTE_BUFFER));
private static final int SEGMENT_SIZE = 1024 * 1024; // (int) N.ONE_MB;
private static final int MIN_BLOCK_SIZE = 256;
private static final int MAX_BLOCK_SIZE = 8192; // 8K
private static final Unsafe UNSAFE;
static {
try {
final Field f = Unsafe.class.getDeclaredField("theUnsafe");
f.setAccessible(true);
UNSAFE = (Unsafe) f.get(null);
} catch (Exception e) {
throw new RuntimeException("Failed to initialize Unsafe", e);
}
}
private static final int BYTE_ARRAY_BASE = UNSAFE.arrayBaseOffset(byte[].class);
private static final ScheduledExecutorService scheduledExecutor;
static {
final ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(IOUtil.CPU_CORES);
executor.setRemoveOnCancelPolicy(true);
scheduledExecutor = MoreExecutors.getExitingScheduledExecutorService(executor);
}
private ScheduledFuture scheduleFuture;
private final long _capacityB;
private final long _startPtr;
private final Segment[] _segments;
private final BitSet _segmentBitSet = new BitSet();
private final Map> _segmentQueueMap = new ConcurrentHashMap<>();
private final Deque _queue256 = new LinkedList<>();
private final Deque _queue384 = new LinkedList<>();
private final Deque _queue512 = new LinkedList<>();
private final Deque _queue640 = new LinkedList<>();
private final Deque _queue768 = new LinkedList<>();
private final Deque _queue896 = new LinkedList<>();
private final Deque _queue1024 = new LinkedList<>();
private final Deque _queue1280 = new LinkedList<>();
private final Deque _queue1536 = new LinkedList<>();
private final Deque _queue1792 = new LinkedList<>();
private final Deque _queue2048 = new LinkedList<>();
private final Deque _queue2560 = new LinkedList<>();
private final Deque _queue3072 = new LinkedList<>();
private final Deque _queue3584 = new LinkedList<>();
private final Deque _queue4096 = new LinkedList<>();
private final Deque _queue5120 = new LinkedList<>();
private final Deque _queue6144 = new LinkedList<>();
private final Deque _queue7168 = new LinkedList<>();
private final Deque _queue8192 = new LinkedList<>();
private final AsyncExecutor _asyncExecutor = new AsyncExecutor();
private final AtomicInteger _activeVacationTaskCount = new AtomicInteger();
private final KeyedObjectPool> _pool;
/**
* The memory with the specified size of MB will be allocated at application start up.
*
* @param sizeMB
*/
public OffHeapCache(int sizeMB) {
this(sizeMB, 3000);
}
/**
* The memory with the specified size of MB will be allocated at application start up.
*
* @param sizeMB
* @param evictDelay unit is milliseconds
*/
public OffHeapCache(int sizeMB, long evictDelay) {
this(sizeMB, evictDelay, DEFAULT_LIVE_TIME, DEFAULT_MAX_IDLE_TIME);
}
/**
* The memory with the specified size of MB will be allocated at application start up.
*
* @param sizeMB
* @param evictDelay unit is milliseconds
* @param defaultLiveTime unit is milliseconds
* @param defaultMaxIdleTime unit is milliseconds
*/
public OffHeapCache(int sizeMB, long evictDelay, long defaultLiveTime, long defaultMaxIdleTime) {
super(defaultLiveTime, defaultMaxIdleTime);
this._capacityB = sizeMB * (1024L * 1024L); // N.ONE_MB;
// ByteBuffer.allocateDirect((int) capacity);
_startPtr = UNSAFE.allocateMemory(_capacityB);
_segments = new Segment[(int) (_capacityB / SEGMENT_SIZE)];
for (int i = 0, len = _segments.length; i < len; i++) {
_segments[i] = new Segment(_startPtr + i * SEGMENT_SIZE);
}
_pool = PoolFactory.createKeyedObjectPool((int) (_capacityB / MIN_BLOCK_SIZE), evictDelay);
if (evictDelay > 0) {
final Runnable evictTask = new Runnable() {
@Override
public void run() {
// Evict from the pool
try {
evict();
} catch (Exception e) {
// ignore
if (logger.isWarnEnabled()) {
logger.warn(AbacusException.getErrorMsg(e));
}
}
}
};
scheduleFuture = scheduledExecutor.scheduleWithFixedDelay(evictTask, evictDelay, evictDelay, TimeUnit.MILLISECONDS);
}
Runtime.getRuntime().addShutdownHook(new Thread() {
@Override
public void run() {
logger.warn("Starting to shutdown task in OffHeapCache");
try {
close();
} finally {
logger.warn("Completed to shutdown task in OffHeapCache");
}
}
});
}
@Override
public V gett(K k) {
final Wrapper w = _pool.get(k);
return w == null ? null : w.read();
}
private static void copyFromMemory(final long startPtr, final byte[] bytes, int destOffset, int len) {
UNSAFE.copyMemory(null, startPtr, bytes, destOffset, len);
}
@Override
public boolean put(K k, V v, long liveTime, long maxIdleTime) {
final Type type = N.typeOf(v.getClass());
Wrapper w = null;
// final byte[] bytes = parser.serialize(v).getBytes();
ByteArrayOutputStream os = null;
byte[] bytes = null;
int size = 0;
if (type.isPrimitiveByteArray()) {
bytes = (byte[]) v;
size = bytes.length;
} else if (type.isByteBuffer()) {
bytes = bbType.byteArrayOf((ByteBuffer) v);
size = bytes.length;
} else {
os = Objectory.createByteArrayOutputStream();
parser.serialize(os, v);
bytes = os.array();
size = os.size();
}
if (size <= MAX_BLOCK_SIZE) {
final AvaialbeSegment availableSegment = getAvailableSegment(size);
if (availableSegment == null) {
Objectory.recycle(os);
vacate();
return false;
}
final long startPtr = availableSegment.segment.startPtr + availableSegment.availableBlockIndex * availableSegment.segment.sizeOfBlock;
boolean isOK = false;
try {
copyToMemory(bytes, BYTE_ARRAY_BASE, startPtr, size);
isOK = true;
} finally {
Objectory.recycle(os);
if (isOK == false) {
availableSegment.release();
return false;
}
}
w = new SWrapper<>(type, liveTime, maxIdleTime, size, availableSegment.segment, startPtr);
} else {
final List> segmentResult = new ArrayList<>(size / MAX_BLOCK_SIZE + 1);
int copiedSize = 0;
int srcOffset = BYTE_ARRAY_BASE;
try {
while (copiedSize < size) {
final int sizeToCopy = size - copiedSize > MAX_BLOCK_SIZE ? MAX_BLOCK_SIZE : size - copiedSize;
final AvaialbeSegment availableSegment = getAvailableSegment(sizeToCopy);
if (availableSegment == null) {
vacate();
return false;
}
final long startPtr = availableSegment.segment.startPtr + availableSegment.availableBlockIndex * availableSegment.segment.sizeOfBlock;
boolean isOK = false;
try {
copyToMemory(bytes, srcOffset, startPtr, sizeToCopy);
srcOffset += sizeToCopy;
copiedSize += sizeToCopy;
isOK = true;
} finally {
if (isOK == false) {
availableSegment.release();
return false;
}
}
segmentResult.add(N.newImmutableEntry(startPtr, availableSegment.segment));
}
w = new MWrapper<>(type, liveTime, maxIdleTime, size, segmentResult);
} finally {
Objectory.recycle(os);
if (w == null) {
for (Map.Entry entry : segmentResult) {
Segment segment = entry.getValue();
segment.release((int) ((entry.getKey() - segment.startPtr) / segment.sizeOfBlock));
}
}
}
}
boolean result = false;
try {
result = _pool.put(k, w);
} finally {
if (!result) {
w.destroy();
}
}
return result;
}
// TODO: performance tuning for concurrent put.
private AvaialbeSegment getAvailableSegment(int size) {
Deque queue = null;
int blockSize = 0;
if (size <= 256) {
queue = _queue256;
blockSize = 256;
} else if (size <= 384) {
queue = _queue384;
blockSize = 384;
} else if (size <= 512) {
queue = _queue512;
blockSize = 512;
} else if (size <= 640) {
queue = _queue640;
blockSize = 640;
} else if (size <= 768) {
queue = _queue768;
blockSize = 768;
} else if (size <= 896) {
queue = _queue896;
blockSize = 896;
} else if (size <= 1024) {
queue = _queue1024;
blockSize = 1024;
} else if (size <= 1280) {
queue = _queue1280;
blockSize = 1280;
} else if (size <= 1536) {
queue = _queue1536;
blockSize = 1536;
} else if (size <= 1792) {
queue = _queue1792;
blockSize = 1792;
} else if (size <= 2048) {
queue = _queue2048;
blockSize = 2048;
} else if (size <= 2560) {
queue = _queue2560;
blockSize = 2560;
} else if (size <= 3072) {
queue = _queue3072;
blockSize = 3072;
} else if (size <= 3584) {
queue = _queue3584;
blockSize = 3584;
} else if (size <= 4096) {
queue = _queue4096;
blockSize = 4096;
} else if (size <= 5120) {
queue = _queue5120;
blockSize = 5120;
} else if (size <= 6144) {
queue = _queue6144;
blockSize = 6144;
} else if (size <= 7168) {
queue = _queue7168;
blockSize = 7168;
} else if (size <= 8192) {
queue = _queue8192;
blockSize = 8192;
} else {
throw new RuntimeException("Unsupported object size: " + size);
}
Segment segment = null;
int availableBlockIndex = -1;
synchronized (queue) {
Iterator iterator = queue.iterator();
Iterator descendingIterator = queue.descendingIterator();
int half = queue.size() / 2 + 1;
int cnt = 0;
while (iterator.hasNext() && half-- > 0) {
cnt++;
segment = iterator.next();
if ((availableBlockIndex = segment.allocate()) >= 0) {
if (cnt > 3) {
iterator.remove();
queue.addFirst(segment);
}
break;
}
segment = descendingIterator.next();
if ((availableBlockIndex = segment.allocate()) >= 0) {
if (cnt > 3) {
descendingIterator.remove();
queue.addFirst(segment);
}
break;
}
}
if (availableBlockIndex < 0) {
synchronized (_segmentBitSet) {
int nextSegmentIndex = _segmentBitSet.nextClearBit(0);
if (nextSegmentIndex >= _segments.length) {
return null; // No space available;
}
segment = _segments[nextSegmentIndex];
_segmentBitSet.set(nextSegmentIndex);
_segmentQueueMap.put(nextSegmentIndex, queue);
segment.sizeOfBlock = blockSize;
queue.addFirst(segment);
availableBlockIndex = segment.allocate();
}
}
}
return new AvaialbeSegment(segment, availableBlockIndex);
}
private static void copyToMemory(final byte[] srcBytes, int srcOffset, final long startPtr, final int len) {
UNSAFE.copyMemory(srcBytes, srcOffset, null, startPtr, len);
}
private void vacate() {
if (_activeVacationTaskCount.get() > 0) {
return;
}
synchronized (_activeVacationTaskCount) {
if (_activeVacationTaskCount.get() > 0) {
return;
}
_activeVacationTaskCount.incrementAndGet();
_asyncExecutor.execute(new Try.Runnable() {
@Override
public void run() {
try {
_pool.vacate();
evict();
// wait for couple of seconds to avoid the second vacation which just arrives before the this vacation is done.
N.sleep(3000);
} finally {
_activeVacationTaskCount.decrementAndGet();
}
}
});
}
}
@Override
public void remove(K k) {
final Wrapper w = _pool.remove(k);
if (w != null) {
w.destroy();
}
}
@Override
public boolean containsKey(K k) {
return _pool.containsKey(k);
}
@Override
public Set keySet() {
return _pool.keySet();
}
@Override
public int size() {
return _pool.size();
}
@Override
public void clear() {
_pool.clear();
}
@Override
public void close() {
if (_pool.isClosed()) {
return;
}
try {
if (scheduleFuture != null) {
scheduleFuture.cancel(true);
}
} finally {
try {
_pool.close();
} finally {
UNSAFE.freeMemory(_startPtr);
}
}
}
@Override
public boolean isClosed() {
return _pool.isClosed();
}
/**
* recycle the empty Segment.
*
*/
protected void evict() {
for (int i = 0, len = _segments.length; i < len; i++) {
if (_segments[i].blockBitSet.isEmpty()) {
final Deque queue = _segmentQueueMap.get(i);
if (queue != null) {
synchronized (queue) {
if (_segments[i].blockBitSet.isEmpty()) {
synchronized (_segmentBitSet) {
queue.remove(_segments[i]);
_segmentQueueMap.remove(i);
_segmentBitSet.clear(i);
}
}
}
}
}
}
}
private static abstract class Wrapper extends AbstractPoolable {
final Type type;
final int size;
Wrapper(final Type type, long liveTime, long maxIdleTime, int size) {
super(liveTime, maxIdleTime);
this.type = type;
this.size = size;
}
abstract T read();
}
private static final class SWrapper extends Wrapper {
private Segment segment;
private final long startPtr;
SWrapper(final Type type, long liveTime, long maxIdleTime, int size, Segment segment, long startPtr) {
super(type, liveTime, maxIdleTime, size);
this.segment = segment;
this.startPtr = startPtr;
}
@Override
T read() {
synchronized (this) {
if (segment == null) {
return null;
}
final byte[] bytes = new byte[size];
copyFromMemory(startPtr, bytes, BYTE_ARRAY_BASE, size);
// it's destroyed after read from memory. dirty data may be read.
if (type.isPrimitiveByteArray()) {
return this.segment == null ? null : (T) bytes;
} else if (type.isByteBuffer()) {
return this.segment == null ? null : (T) bbType.valueOf(bytes);
} else {
return this.segment == null ? null : parser.deserialize(type.clazz(), new ByteArrayInputStream(bytes));
}
}
}
@Override
public void destroy() {
synchronized (this) {
if (segment != null) {
segment.release((int) ((startPtr - segment.startPtr) / segment.sizeOfBlock));
segment = null;
}
}
}
}
private static final class MWrapper extends Wrapper {
private List> segments;
MWrapper(final Type type, long liveTime, long maxIdleTime, int size, List> segments) {
super(type, liveTime, maxIdleTime, size);
this.segments = segments;
}
@Override
T read() {
synchronized (this) {
if (N.isNullOrEmpty(segments)) {
return null;
}
final List> segments = this.segments;
final byte[] bytes = new byte[size];
int size = this.size;
int destOffset = BYTE_ARRAY_BASE;
for (Map.Entry entry : segments) {
final long startPtr = entry.getKey();
final Segment segment = entry.getValue();
final int sizeToCopy = size > segment.sizeOfBlock ? segment.sizeOfBlock : size;
copyFromMemory(startPtr, bytes, destOffset, sizeToCopy);
destOffset += sizeToCopy;
size -= sizeToCopy;
}
// should never happen.
if (size != 0) {
throw new RuntimeException(
"Unknown error happening when retrieve value. The remaining size is " + size + " after finishing fetch data from all segments");
}
// it's destroyed after read from memory. dirty data may be read.
if (type.isPrimitiveByteArray()) {
return this.segments == null ? null : (T) bytes;
} else if (type.isByteBuffer()) {
return this.segments == null ? null : (T) (T) bbType.valueOf(bytes);
} else {
return this.segments == null ? null : parser.deserialize(type.clazz(), new ByteArrayInputStream(bytes));
}
}
}
@Override
public void destroy() {
synchronized (this) {
if (segments != null) {
for (Map.Entry entry : segments) {
final Segment segment = entry.getValue();
segment.release((int) ((entry.getKey() - segment.startPtr) / segment.sizeOfBlock));
}
segments = null;
}
}
}
}
private static final class Segment {
private final BitSet blockBitSet = new BitSet();
private final long startPtr;
private int sizeOfBlock;
public Segment(long segmentStartPtr) {
this.startPtr = segmentStartPtr;
}
public int allocate() {
synchronized (blockBitSet) {
int result = blockBitSet.nextClearBit(0);
if (result >= SEGMENT_SIZE / sizeOfBlock) {
return -1;
}
blockBitSet.set(result);
return result;
}
}
public void release(int blockIndex) {
synchronized (blockBitSet) {
blockBitSet.clear(blockIndex);
}
}
//
// public void clear() {
// synchronized (blockBitSet) {
// blockBitSet.clear();
// sizeOfBlock = 0;
// }
// }
}
private static final class AvaialbeSegment {
final Segment segment;
final int availableBlockIndex;
AvaialbeSegment(final Segment segment, final int availableBlockIndex) {
this.segment = segment;
this.availableBlockIndex = availableBlockIndex;
}
void release() {
this.segment.release(availableBlockIndex);
}
}
}