org.mapdb.Volume Maven / Gradle / Ivy
/*
* Copyright (c) 2012 Jan Kotek
*
* Licensed 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 org.mapdb;
import java.io.*;
import java.lang.ref.Reference;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.util.*;
import java.util.concurrent.locks.ReentrantLock;
import java.util.logging.Level;
/**
* MapDB abstraction over raw storage (file, disk partition, memory etc...).
*
* Implementations needs to be thread safe (especially
'ensureAvailable') operation.
* However updates do not have to be atomic, it is clients responsibility
* to ensure two threads are not writing/reading into the same location.
*
* @author Jan Kotek
*/
public abstract class Volume {
public static final int CHUNK_SHIFT = 30;
public static final int CHUNK_SIZE = 1<< CHUNK_SHIFT;
public static final int CHUNK_SIZE_MOD_MASK = CHUNK_SIZE -1;
/**
* Check space allocated by Volume is bigger or equal to given offset.
* So it is safe to write into smaller offsets.
*
* @throws IOError if Volume can not be expanded beyond given offset
* @param offset
*/
public void ensureAvailable(final long offset){
if(!tryAvailable(offset))
throw new IOError(new IOException("no free space to expand Volume"));
}
abstract public boolean tryAvailable(final long offset);
abstract public void putLong(final long offset, final long value);
abstract public void putInt(long offset, int value);
abstract public void putByte(final long offset, final byte value);
abstract public void putData(final long offset, final byte[] src, int srcPos, int srcSize);
abstract public void putData(final long offset, final ByteBuffer buf);
abstract public long getLong(final long offset);
abstract public int getInt(long offset);
abstract public byte getByte(final long offset);
abstract public DataInput2 getDataInput(final long offset, final int size);
abstract public void close();
abstract public void sync();
public abstract boolean isEmpty();
public abstract void deleteFile();
public abstract boolean isSliced();
public final void putUnsignedShort(final long offset, final int value){
putByte(offset, (byte) (value>>8));
putByte(offset+1, (byte) (value));
}
public final int getUnsignedShort(long offset) {
return (( (getByte(offset) & 0xff) << 8) |
( (getByte(offset+1) & 0xff)));
}
public int getUnsignedByte(long offset) {
return getByte(offset) & 0xff;
}
public void putUnsignedByte(long offset, int b) {
putByte(offset, (byte)(b & 0xff));
}
/**
* Reads a long from the indicated position
*/
public long getSixLong(long pos) {
return
((long) (getByte(pos + 0) & 0xff) << 40) |
((long) (getByte(pos + 1) & 0xff) << 32) |
((long) (getByte(pos + 2) & 0xff) << 24) |
((long) (getByte(pos + 3) & 0xff) << 16) |
((long) (getByte(pos + 4) & 0xff) << 8) |
((long) (getByte(pos + 5) & 0xff) << 0);
}
/**
* Writes a long to the indicated position
*/
public void putSixLong(long pos, long value) {
assert(value>=0 && (value>>>6*8)==0): "value does not fit";
//TODO read/write as integer+short, might be faster
putByte(pos + 0, (byte) (0xff & (value >> 40)));
putByte(pos + 1, (byte) (0xff & (value >> 32)));
putByte(pos + 2, (byte) (0xff & (value >> 24)));
putByte(pos + 3, (byte) (0xff & (value >> 16)));
putByte(pos + 4, (byte) (0xff & (value >> 8)));
putByte(pos + 5, (byte) (0xff & (value >> 0)));
}
/**
* Writes packed long at given position and returns number of bytes used.
*/
public int putPackedLong(long pos, long value) {
assert(value>=0):"negative value";
int ret = 0;
while ((value & ~0x7FL) != 0) {
putUnsignedByte(pos+(ret++), (((int) value & 0x7F) | 0x80));
value >>>= 7;
}
putUnsignedByte(pos + (ret++), (byte) value);
return ret;
}
/** returns underlying file if it exists */
abstract public File getFile();
public long getPackedLong(long pos){
//TODO unrolled version?
long result = 0;
for (int offset = 0; offset < 64; offset += 7) {
long b = getUnsignedByte(pos++);
result |= (b & 0x7F) << offset;
if ((b & 0x80) == 0) {
return result;
}
}
throw new AssertionError("Malformed long.");
}
/**
* Factory which creates two/three volumes used by each MapDB Storage Engine
*/
public static interface Factory {
Volume createIndexVolume();
Volume createPhysVolume();
Volume createTransLogVolume();
}
public static Volume volumeForFile(File f, boolean useRandomAccessFile, boolean readOnly, long sizeLimit, boolean fullChunkAllocation) {
return useRandomAccessFile ?
new FileChannelVol(f, readOnly,sizeLimit, fullChunkAllocation):
new MappedFileVol(f, readOnly,sizeLimit,fullChunkAllocation);
}
public static Factory fileFactory(final boolean readOnly, final int rafMode, final File indexFile, final long sizeLimit,
final boolean fullChunkAllocation){
return fileFactory(readOnly, rafMode, sizeLimit, fullChunkAllocation, indexFile,
new File(indexFile.getPath() + StoreDirect.DATA_FILE_EXT),
new File(indexFile.getPath() + StoreWAL.TRANS_LOG_FILE_EXT));
}
public static Factory fileFactory(final boolean readOnly,
final int rafMode,
final long sizeLimit,
final boolean fullChunkAllocation,
final File indexFile,
final File physFile,
final File transLogFile) {
return new Factory() {
@Override
public Volume createIndexVolume() {
return volumeForFile(indexFile, rafMode>1, readOnly, sizeLimit, fullChunkAllocation);
}
@Override
public Volume createPhysVolume() {
return volumeForFile(physFile, rafMode>0, readOnly, sizeLimit, fullChunkAllocation);
}
@Override
public Volume createTransLogVolume() {
if(readOnly && !transLogFile.exists())
return null;
return volumeForFile(transLogFile, rafMode>0, readOnly, sizeLimit, fullChunkAllocation);
}
};
}
public static Factory memoryFactory(final boolean useDirectBuffer, final long sizeLimit, final boolean fullChunkAllocation) {
return new Factory() {
@Override public synchronized Volume createIndexVolume() {
return new MemoryVol(useDirectBuffer, sizeLimit,fullChunkAllocation);
}
@Override public synchronized Volume createPhysVolume() {
return new MemoryVol(useDirectBuffer, sizeLimit,fullChunkAllocation);
}
@Override public synchronized Volume createTransLogVolume() {
return new MemoryVol(useDirectBuffer, sizeLimit,fullChunkAllocation);
}
};
}
/**
* Abstract Volume over bunch of ByteBuffers
* It leaves ByteBufferVol details (allocation, disposal) on subclasses.
* Most methods are final for better performance (JIT compiler can inline those).
*/
abstract static public class ByteBufferVol extends Volume{
protected final ReentrantLock growLock = new ReentrantLock(CC.FAIR_LOCKS);
protected final long sizeLimit;
protected final boolean hasLimit;
protected final boolean fullChunkAllocation;
protected volatile ByteBuffer[] chunks;
protected final boolean readOnly;
protected ByteBufferVol(boolean readOnly, long sizeLimit, boolean fullChunkAllocation) {
this.readOnly = readOnly;
this.sizeLimit = sizeLimit;
this.fullChunkAllocation = fullChunkAllocation;
this.hasLimit = sizeLimit>0;
}
@Override
public final boolean tryAvailable(long offset) {
if(hasLimit&&offset>sizeLimit) return false;
int chunkPos = (int) (offset >>> CHUNK_SHIFT);
//check for most common case, this is already mapped
if(chunkPos< chunks.length && chunks[chunkPos]!=null &&
chunks[chunkPos].capacity()>=(offset&Volume.CHUNK_SIZE_MOD_MASK)){
return true;
}
growLock.lock();
try{
//check second time
if(chunkPos< chunks.length && chunks[chunkPos]!=null &&
chunks[chunkPos].capacity()>=(offset&Volume.CHUNK_SIZE_MOD_MASK))
return true;
ByteBuffer[] chunks2 = chunks;
//grow array if necessary
if(chunkPos>=chunks2.length){
chunks2 = Arrays.copyOf(chunks2, Math.max(chunkPos+1, chunks2.length * 2));
}
//just remap file buffer
if( chunks2[chunkPos] == null){
//make sure previous buffer is fully expanded
if(chunkPos>0){
ByteBuffer oldPrev = chunks2[chunkPos-1];
if(oldPrev == null || oldPrev.capacity()!= CHUNK_SIZE){
chunks2[chunkPos-1] = makeNewBuffer(1L*chunkPos* CHUNK_SIZE -1,chunks2);
}
}
}
ByteBuffer newChunk = makeNewBuffer(offset, chunks2);
if(readOnly)
newChunk = newChunk.asReadOnlyBuffer();
chunks2[chunkPos] = newChunk;
chunks = chunks2;
}finally{
growLock.unlock();
}
return true;
}
protected abstract ByteBuffer makeNewBuffer(long offset, ByteBuffer[] buffers2);
@Override public final void putLong(final long offset, final long value) {
chunks[(int)(offset >>> CHUNK_SHIFT)].putLong((int) (offset & Volume.CHUNK_SIZE_MOD_MASK), value);
}
@Override public final void putInt(final long offset, final int value) {
chunks[(int)(offset >>> CHUNK_SHIFT)].putInt((int) (offset & Volume.CHUNK_SIZE_MOD_MASK), value);
}
@Override public final void putByte(final long offset, final byte value) {
chunks[(int)(offset >>> CHUNK_SHIFT)].put((int) (offset & Volume.CHUNK_SIZE_MOD_MASK), value);
}
@Override public void putData(final long offset, final byte[] src, int srcPos, int srcSize){
final ByteBuffer b1 = chunks[(int)(offset >>> CHUNK_SHIFT)].duplicate();
final int bufPos = (int) (offset&Volume.CHUNK_SIZE_MOD_MASK);
b1.position(bufPos);
b1.put(src, srcPos, srcSize);
}
@Override public final void putData(final long offset, final ByteBuffer buf) {
final ByteBuffer b1 = chunks[(int)(offset >>> CHUNK_SHIFT)].duplicate();
final int bufPos = (int) (offset&Volume.CHUNK_SIZE_MOD_MASK);
//no overlap, so just write the value
b1.position(bufPos);
b1.put(buf);
}
@Override final public long getLong(long offset) {
return chunks[(int)(offset >>> CHUNK_SHIFT)].getLong((int) (offset&Volume.CHUNK_SIZE_MOD_MASK));
}
@Override final public int getInt(long offset) {
return chunks[(int)(offset >>> CHUNK_SHIFT)].getInt((int) (offset&Volume.CHUNK_SIZE_MOD_MASK));
}
@Override public final byte getByte(long offset) {
return chunks[(int)(offset >>> CHUNK_SHIFT)].get((int) (offset&Volume.CHUNK_SIZE_MOD_MASK));
}
@Override
public final DataInput2 getDataInput(long offset, int size) {
return new DataInput2(chunks[(int)(offset >>> CHUNK_SHIFT)], (int) (offset&Volume.CHUNK_SIZE_MOD_MASK));
}
@Override
public boolean isEmpty() {
return chunks[0]==null || chunks[0].capacity()==0;
}
@Override
public boolean isSliced(){
return true;
}
/**
* Hack to unmap MappedByteBuffer.
* Unmap is necessary on Windows, otherwise file is locked until JVM exits or BB is GCed.
* There is no public JVM API to unmap buffer, so this tries to use SUN proprietary API for unmap.
* Any error is silently ignored (for example SUN API does not exist on Android).
*/
protected void unmap(MappedByteBuffer b){
try{
if(unmapHackSupported){
// need to dispose old direct buffer, see bug
// http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4724038
Method cleanerMethod = b.getClass().getMethod("cleaner", new Class[0]);
if(cleanerMethod!=null){
cleanerMethod.setAccessible(true);
Object cleaner = cleanerMethod.invoke(b, new Object[0]);
if(cleaner!=null){
Method clearMethod = cleaner.getClass().getMethod("clean", new Class[0]);
if(cleanerMethod!=null)
clearMethod.invoke(cleaner, new Object[0]);
}
}
}
}catch(Exception e){
unmapHackSupported = false;
//TODO exception handling
//Utils.LOG.log(Level.WARNING, "ByteBufferVol Unmap failed", e);
}
}
private static boolean unmapHackSupported = true;
static{
try{
unmapHackSupported =
SerializerPojo.classForName("sun.nio.ch.DirectBuffer")!=null;
}catch(Exception e){
unmapHackSupported = false;
}
}
}
public static final class MappedFileVol extends ByteBufferVol {
protected final File file;
protected final FileChannel fileChannel;
protected final FileChannel.MapMode mapMode;
protected final java.io.RandomAccessFile raf;
protected ReferenceQueue unreleasedQueue = new ReferenceQueue();
protected Set> unreleasedChunks = new LinkedHashSet>();
static final int BUF_SIZE_INC = 1024*1024;
public MappedFileVol(File file, boolean readOnly, long sizeLimit, boolean fullChunkAllocation) {
super(readOnly, sizeLimit, fullChunkAllocation);
this.file = file;
this.mapMode = readOnly? FileChannel.MapMode.READ_ONLY: FileChannel.MapMode.READ_WRITE;
try {
this.raf = new java.io.RandomAccessFile(file, readOnly?"r":"rw");
this.fileChannel = raf.getChannel();
final long fileSize = fileChannel.size();
if(fileSize>0){
//map existing data
chunks = new ByteBuffer[(int) (1+(fileSize>>> CHUNK_SHIFT))];
for(int i=0;i<=fileSize>>> CHUNK_SHIFT;i++){
final long offset = 1L* CHUNK_SIZE *i;
chunks[i] = fileChannel.map(mapMode, offset, Math.min(CHUNK_SIZE, fileSize-offset));
if(mapMode == FileChannel.MapMode.READ_ONLY)
chunks[i] = chunks[i].asReadOnlyBuffer();
//TODO what if 'fileSize % 8 != 0'?
}
}else{
chunks = new ByteBuffer[1];
// chunks[0] = fileChannel.map(mapMode, 0, INITIAL_SIZE);
// if(mapMode == FileChannel.MapMode.READ_ONLY)
// chunks[0] = chunks[0].asReadOnlyBuffer();
}
} catch (IOException e) {
throw new IOError(e);
}
}
@Override
public void close() {
growLock.lock();
try{
fileChannel.close();
raf.close();
if(!readOnly)
sync();
for(Reference rb: unreleasedChunks){
MappedByteBuffer b = rb.get();
if(b==null) continue;
unmap(b);
}
for(ByteBuffer b: chunks){
if(b!=null && (b instanceof MappedByteBuffer)){
unmap((MappedByteBuffer) b);
}
}
unreleasedChunks = null;
unreleasedQueue = null;
chunks = null;
} catch (IOException e) {
throw new IOError(e);
}finally{
growLock.unlock();
}
}
@Override
public void sync() {
if(readOnly) return;
growLock.lock();
try{
//clear GC references
for(Reference ref=unreleasedQueue.poll();ref!=null; ref=unreleasedQueue.poll()){
unreleasedChunks.remove(ref);
}
for(Reference rb: unreleasedChunks){
MappedByteBuffer b = rb.get();
if(b==null) continue;
b.force();
}
for(ByteBuffer b: chunks){
if(b!=null && (b instanceof MappedByteBuffer)){
((MappedByteBuffer) b).force();
}
}
}finally{
growLock.unlock();
}
}
@Override
public boolean isEmpty() {
return chunks[0]==null || chunks[0].capacity()==0;
}
@Override
public void deleteFile() {
file.delete();
}
@Override
public File getFile() {
return file;
}
@Override
protected ByteBuffer makeNewBuffer(long offset, ByteBuffer[] buffers2) {
assert (growLock.isHeldByCurrentThread());
try {
//create new chunk
long newChunkSize = offset&Volume.CHUNK_SIZE_MOD_MASK;
int round = offset(buf, unreleasedQueue));
for(Reference ref=unreleasedQueue.poll();ref!=null; ref=unreleasedQueue.poll()){
unreleasedChunks.remove(ref);
}
return buf;
} catch (IOException e) {
if(e.getCause()!=null && e.getCause() instanceof OutOfMemoryError){
throw new RuntimeException("File could not be mapped to memory, common problem on 32bit JVM. Use `DBMaker.newRandomAccessFileDB()` as workaround",e);
}
throw new IOError(e);
}
}
}
public static final class MemoryVol extends ByteBufferVol {
protected final boolean useDirectBuffer;
@Override
public String toString() {
return super.toString()+",direct="+useDirectBuffer;
}
public MemoryVol(final boolean useDirectBuffer, final long sizeLimit, final boolean fullChunkAllocation) {
super(false,sizeLimit, fullChunkAllocation);
this.useDirectBuffer = useDirectBuffer;
// ByteBuffer b0 = useDirectBuffer?
// ByteBuffer.allocateDirect(INITIAL_SIZE) :
// ByteBuffer.allocate(INITIAL_SIZE);
// chunks = new ByteBuffer[]{b0};
chunks =new ByteBuffer[1];
}
@Override protected ByteBuffer makeNewBuffer(long offset, ByteBuffer[] buffers2) {
int curSize = (int) (offset & Volume.CHUNK_SIZE_MOD_MASK);
int newBufSize = 1 << (32 - Integer.numberOfLeadingZeros(curSize - 1)); //next pow of two
if(fullChunkAllocation && newBufSize% CHUNK_SIZE !=0){
//round newBufSize to multiple of BUF_SIZE_INC
newBufSize += CHUNK_SIZE -newBufSize% CHUNK_SIZE;
}
//double size of existing in-memory-buffer
ByteBuffer newBuf = useDirectBuffer?
ByteBuffer.allocateDirect(newBufSize):
ByteBuffer.allocate(newBufSize);
final int buffersPos = (int) (offset >>> CHUNK_SHIFT);
ByteBuffer oldBuffer = buffers2[buffersPos];
if(oldBuffer!=null){
//copy old buffer if it exists
oldBuffer = oldBuffer.duplicate();
oldBuffer.rewind();
newBuf.put(oldBuffer);
}
return newBuf;
}
@Override public void close() {
growLock.lock();
try{
for(ByteBuffer b: chunks){
if(b!=null && (b instanceof MappedByteBuffer)){
unmap((MappedByteBuffer)b);
}
}
chunks = null;
}finally{
growLock.unlock();
}
}
@Override public void sync() {}
@Override public void deleteFile() {}
@Override
public File getFile() {
return null;
}
}
/**
* Volume which uses FileChannel.
* Uses global lock and does not use mapped memory.
*/
public static final class FileChannelVol extends Volume {
protected final File file;
protected FileChannel channel;
protected final boolean readOnly;
protected final long sizeLimit;
protected final boolean hasLimit;
protected final boolean fullChunkAllocation;
protected volatile long size;
protected Object growLock = new Object();
public FileChannelVol(File file, boolean readOnly, long sizeLimit, boolean fullChunkAllocation){
this.file = file;
this.readOnly = readOnly;
this.sizeLimit = sizeLimit;
this.fullChunkAllocation = fullChunkAllocation;
this.hasLimit = sizeLimit>0;
try {
channel = new RandomAccessFile(file, readOnly?"r":"rw").getChannel();
size = channel.size();
} catch (IOException e) {
throw new IOError(e);
}
}
@Override
public boolean tryAvailable(long offset) {
if(hasLimit && offset>sizeLimit) return false;
if(fullChunkAllocation && offset% CHUNK_SIZE !=0)
offset += CHUNK_SIZE - offset% CHUNK_SIZE;
if(offset>size)synchronized (growLock){
try {
channel.truncate(offset);
size = offset;
} catch (IOException e) {
throw new IOError(e);
}
}
return true;
}
protected void writeFully(long offset, ByteBuffer buf) throws IOException {
int remaining = buf.limit()-buf.position();
while(remaining>0){
int write = channel.write(buf, offset);
if(write<0) throw new EOFException();
remaining-=write;
}
}
@Override
public final void putSixLong(long offset, long value) {
assert(value>=0 && (value>>>6*8)==0): "value does not fit";
try{
ByteBuffer buf = ByteBuffer.allocate(6);
buf.put(0, (byte) (0xff & (value >> 40)));
buf.put(1, (byte) (0xff & (value >> 32)));
buf.put(2, (byte) (0xff & (value >> 24)));
buf.put(3, (byte) (0xff & (value >> 16)));
buf.put(4, (byte) (0xff & (value >> 8)));
buf.put(5, (byte) (0xff & (value >> 0)));
writeFully(offset, buf);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void putLong(long offset, long value) {
try{
ByteBuffer buf = ByteBuffer.allocate(8);
buf.putLong(0, value);
writeFully(offset, buf);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void putInt(long offset, int value) {
try{
ByteBuffer buf = ByteBuffer.allocate(4);
buf.putInt(0, value);
writeFully(offset, buf);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void putByte(long offset, byte value) {
try{
ByteBuffer buf = ByteBuffer.allocate(1);
buf.put(0, value);
writeFully(offset, buf);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void putData(long offset, byte[] src, int srcPos, int srcSize) {
try{
ByteBuffer buf = ByteBuffer.wrap(src,srcPos, srcSize);
writeFully(offset, buf);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void putData(long offset, ByteBuffer buf) {
try{
writeFully(offset,buf);
}catch(IOException e){
throw new IOError(e);
}
}
protected void readFully(long offset, ByteBuffer buf) throws IOException {
int remaining = buf.limit()-buf.position();
while(remaining>0){
int read = channel.read(buf, offset);
if(read<0) throw new EOFException();
remaining-=read;
}
}
@Override
public final long getSixLong(long offset) {
try{
ByteBuffer buf = ByteBuffer.allocate(6);
readFully(offset,buf);
return ((long) (buf.get(0) & 0xff) << 40) |
((long) (buf.get(1) & 0xff) << 32) |
((long) (buf.get(2) & 0xff) << 24) |
((long) (buf.get(3) & 0xff) << 16) |
((long) (buf.get(4) & 0xff) << 8) |
((long) (buf.get(5) & 0xff) << 0);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public long getLong(long offset) {
try{
ByteBuffer buf = ByteBuffer.allocate(8);
readFully(offset,buf);
return buf.getLong(0);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public int getInt(long offset) {
try{
ByteBuffer buf = ByteBuffer.allocate(4);
readFully(offset,buf);
return buf.getInt(0);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public byte getByte(long offset) {
try{
ByteBuffer buf = ByteBuffer.allocate(1);
readFully(offset,buf);
return buf.get(0);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public DataInput2 getDataInput(long offset, int size) {
try{
ByteBuffer buf = ByteBuffer.allocate(size);
readFully(offset,buf);
return new DataInput2(buf,0);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void close() {
try{
channel.close();
channel = null;
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public void sync() {
try{
channel.force(true);
}catch(IOException e){
throw new IOError(e);
}
}
@Override
public boolean isEmpty() {
try {
return channel==null || channel.size()==0;
} catch (IOException e) {
throw new IOError(e);
}
}
@Override
public void deleteFile() {
file.delete();
}
@Override
public boolean isSliced() {
return false;
}
@Override
public File getFile() {
return file;
}
}
/** transfer data from one volume to second. Second volume will be expanded if needed*/
public static void volumeTransfer(long size, Volume from, Volume to){
int bufSize = 1024*64;
for(long offset=0;offset © 2015 - 2025 Weber Informatics LLC | Privacy Policy