/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.common.buffer.impl;
import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import org.teiid.common.buffer.FileStore;
import org.teiid.common.buffer.StorageManager;
import org.teiid.core.TeiidRuntimeException;
import org.teiid.logging.LogConstants;
import org.teiid.logging.LogManager;
import org.teiid.logging.MessageLevel;
import org.teiid.query.QueryPlugin;
/**
* Represents a FileStore that holds blocks of a fixed size.
*/
class BlockStore {
final long blockSize;
final ConcurrentBitSet blocksInUse;
final FileStore[] stores;
final ReentrantReadWriteLock[] locks;
public BlockStore(StorageManager storageManager, int blockSize, int blockCountLog, int concurrencyLevel) {
this.blockSize = blockSize;
int blockCount = 1 << blockCountLog;
this.blocksInUse = new ConcurrentBitSet(blockCount, concurrencyLevel);
this.blocksInUse.setCompact(true);
this.stores = new FileStore[concurrencyLevel];
this.locks = new ReentrantReadWriteLock[concurrencyLevel];
for (int i = 0; i < stores.length; i++) {
this.stores[i] = storageManager.createFileStore(String.valueOf(blockSize) + '_' + i);
this.locks[i] = new ReentrantReadWriteLock();
}
}
int getAndSetNextClearBit(PhysicalInfo info) {
int result = blocksInUse.getAndSetNextClearBit();
if (result == -1) {
throw new TeiidRuntimeException(QueryPlugin.Event.TEIID30059, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID30059, blockSize));
}
if (LogManager.isMessageToBeRecorded(LogConstants.CTX_BUFFER_MGR, MessageLevel.DETAIL)) {
LogManager.logDetail(LogConstants.CTX_BUFFER_MGR, "Allocating storage data block", result, "of size", blockSize, "to", info); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
}
return result;
}
int writeToStorageBlock(PhysicalInfo info,
InputStream is) throws IOException {
int block = getAndSetNextClearBit(info);
int segment = block/blocksInUse.getBitsPerSegment();
boolean success = false;
this.locks[segment].writeLock().lock();
try {
FileStore fs = stores[segment];
long blockOffset = (block%blocksInUse.getBitsPerSegment())*blockSize;
//TODO: there is still an extra buffer being created here, we could FileChannels to do better
byte[] b = new byte[BufferFrontedFileStoreCache.BLOCK_SIZE];
int read = 0;
long newLength = blockOffset+blockSize;
if (fs.getLength() < newLength) {
//grow by whole blocks
//TODO: could pad the growth
fs.setLength(newLength);
}
while ((read = is.read(b, 0, b.length)) != -1) {
fs.write(blockOffset, b, 0, read);
blockOffset+=read;
}
success = true;
} finally {
locks[segment].writeLock().unlock();
if (!success) {
blocksInUse.clear(block);
block = BufferFrontedFileStoreCache.EMPTY_ADDRESS;
}
}
return block;
}
}