/**
*Copyright [2009-2010] [dennis zhuang(killme2008@gmail.com)]
*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
*/
/**
*Copyright [2009-2010] [dennis zhuang(killme2008@gmail.com)]
*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 net.rubyeye.xmemcached.impl;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.concurrent.CountDownLatch;
import net.rubyeye.xmemcached.MemcachedOptimizer;
import net.rubyeye.xmemcached.buffer.BufferAllocator;
import net.rubyeye.xmemcached.command.AssocCommandAware;
import net.rubyeye.xmemcached.command.Command;
import net.rubyeye.xmemcached.command.CommandType;
import net.rubyeye.xmemcached.command.OperationStatus;
import net.rubyeye.xmemcached.command.binary.BaseBinaryCommand;
import net.rubyeye.xmemcached.command.binary.BinaryGetCommand;
import net.rubyeye.xmemcached.command.binary.BinaryGetMultiCommand;
import net.rubyeye.xmemcached.command.binary.BinarySetMultiCommand;
import net.rubyeye.xmemcached.command.binary.BinaryStoreCommand;
import net.rubyeye.xmemcached.command.binary.OpCode;
import net.rubyeye.xmemcached.command.text.TextGetOneCommand;
import net.rubyeye.xmemcached.monitor.Constants;
import net.rubyeye.xmemcached.monitor.MemcachedClientNameHolder;
import net.rubyeye.xmemcached.monitor.XMemcachedMbeanServer;
import net.rubyeye.xmemcached.utils.ByteUtils;
import net.rubyeye.xmemcached.utils.OpaqueGenerater;
import net.rubyeye.xmemcached.utils.Protocol;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.code.yanf4j.buffer.IoBuffer;
import com.google.code.yanf4j.core.impl.FutureImpl;
/**
* Memcached command optimizer,merge single-get comands to multi-get
* command,merge ByteBuffers to fit the socket's sendBufferSize etc.
*
* @author dennis
*/
public class Optimizer implements OptimizerMBean, MemcachedOptimizer {
public static final int DEFAULT_MERGE_FACTOR = 50;
private int mergeFactor = DEFAULT_MERGE_FACTOR; // default merge factor;
private boolean optimiezeGet = true;
private final boolean optimiezeSet = true;
private boolean optimiezeMergeBuffer = true;
private static final Logger log = LoggerFactory.getLogger(Optimizer.class);
private Protocol protocol = Protocol.Binary;
public Optimizer(Protocol protocol) {
XMemcachedMbeanServer.getInstance().registMBean(
this,
this.getClass().getPackage().getName() + ":type="
+ this.getClass().getSimpleName() + "-"
+ MemcachedClientNameHolder.getName());
this.protocol = protocol;
}
public void setBufferAllocator(BufferAllocator bufferAllocator) {
}
public int getMergeFactor() {
return this.mergeFactor;
}
public void setMergeFactor(int mergeFactor) {
if (this.mergeFactor != mergeFactor) {
log.warn("change mergeFactor from " + this.mergeFactor + " to "
+ mergeFactor);
}
this.mergeFactor = mergeFactor;
}
public boolean isOptimizeGet() {
return this.optimiezeGet;
}
public void setOptimizeGet(boolean optimiezeGet) {
log.warn(optimiezeGet ? "Enable merge get commands"
: "Disable merge get commands");
this.optimiezeGet = optimiezeGet;
}
public boolean isOptimizeMergeBuffer() {
return this.optimiezeMergeBuffer;
}
public void setOptimizeMergeBuffer(boolean optimiezeMergeBuffer) {
log.warn(optimiezeMergeBuffer ? "Enable merge buffers"
: "Disable merge buffers");
this.optimiezeMergeBuffer = optimiezeMergeBuffer;
}
@SuppressWarnings("unchecked")
public Command optimize(final Command currentCommand,
final Queue writeQueue, final Queue<Command> executingCmds,
int sendBufferSize) {
Command optimiezeCommand = currentCommand;
optimiezeCommand = this.optimiezeGet(writeQueue, executingCmds,
optimiezeCommand);
optimiezeCommand = this.optimiezeSet(writeQueue, executingCmds,
optimiezeCommand, sendBufferSize);
optimiezeCommand = this.optimiezeMergeBuffer(optimiezeCommand, writeQueue,
executingCmds, sendBufferSize);
return optimiezeCommand;
}
/**
* merge buffers to fit socket's send buffer size
*
* @param currentCommand
* @return
* @throws InterruptedException
*/
@SuppressWarnings("unchecked")
public final Command optimiezeMergeBuffer(Command optimiezeCommand,
final Queue writeQueue, final Queue<Command> executingCmds,
int sendBufferSize) {
if (log.isDebugEnabled()) {
log.debug("Optimieze merge buffer:" + optimiezeCommand.toString());
}
if (this.optimiezeMergeBuffer
&& optimiezeCommand.getIoBuffer().remaining() < sendBufferSize - 24) {
optimiezeCommand = this.mergeBuffer(optimiezeCommand, writeQueue,
executingCmds, sendBufferSize);
}
return optimiezeCommand;
}
/**
* Merge get operation to multi-get operation
*
* @param currentCmd
* @param mergeCommands
* @return
* @throws InterruptedException
*/
@SuppressWarnings("unchecked")
public final Command optimiezeGet(final Queue writeQueue,
final Queue<Command> executingCmds, Command optimiezeCommand) {
if (optimiezeCommand.getCommandType() == CommandType.GET_ONE
|| optimiezeCommand.getCommandType() == CommandType.GETS_ONE) {
if (this.optimiezeGet) {
optimiezeCommand = this.mergeGetCommands(optimiezeCommand,
writeQueue, executingCmds,
optimiezeCommand.getCommandType());
}
}
return optimiezeCommand;
}
public final Command optimiezeSet(final Queue writeQueue,
final Queue<Command> executingCmds, Command optimiezeCommand,
int sendBufferSize) {
if (this.optimiezeSet
&& optimiezeCommand.getCommandType() == CommandType.SET
&& !optimiezeCommand.isNoreply() && this.protocol == Protocol.Binary) {
optimiezeCommand = this.mergeSetCommands(optimiezeCommand, writeQueue,
executingCmds, optimiezeCommand.getCommandType(),
sendBufferSize);
}
return optimiezeCommand;
}
@SuppressWarnings("unchecked")
private final Command mergeBuffer(final Command firstCommand,
final Queue writeQueue, final Queue<Command> executingCmds,
final int sendBufferSize) {
Command lastCommand = firstCommand;
Command nextCmd = (Command) writeQueue.peek();
if (nextCmd == null) {
return lastCommand;
}
final List<Command> commands = this.getLocalList();
final ByteBuffer firstBuffer = firstCommand.getIoBuffer().buf();
int totalBytes = firstBuffer.remaining();
commands.add(firstCommand);
boolean wasFirst = true;
while (totalBytes + nextCmd.getIoBuffer().remaining() <= sendBufferSize
&& (nextCmd = (Command) writeQueue.peek()) != null) {
if (nextCmd.getStatus() == OperationStatus.WRITING) {
break;
}
if (nextCmd.isCancel()) {
writeQueue.remove();
continue;
}
nextCmd.setStatus(OperationStatus.WRITING);
writeQueue.remove();
if (wasFirst) {
wasFirst = false;
}
// if it is get_one command,try to merge get commands
if ((nextCmd.getCommandType() == CommandType.GET_ONE || nextCmd
.getCommandType() == CommandType.GETS_ONE) && this.optimiezeGet) {
nextCmd = this.mergeGetCommands(nextCmd, writeQueue, executingCmds,
nextCmd.getCommandType());
}
commands.add(nextCmd);
lastCommand = nextCmd;
totalBytes += nextCmd.getIoBuffer().remaining();
if (totalBytes > sendBufferSize) {
break;
}
}
if (commands.size() > 1) {
byte[] buf = new byte[totalBytes];
int offset = 0;
for (Command command : commands) {
byte[] ba = command.getIoBuffer().array();
System.arraycopy(ba, 0, buf, offset, ba.length);
offset += ba.length;
if (command != lastCommand
&& (!command.isNoreply() || command instanceof BaseBinaryCommand)) {
executingCmds.add(command);
}
}
lastCommand.setIoBuffer(IoBuffer.wrap(buf));
}
return lastCommand;
}
private final ThreadLocal<List<Command>> threadLocal = new ThreadLocal<List<Command>>() {
@Override
protected List<Command> initialValue() {
return new ArrayList<Command>(Optimizer.this.mergeFactor);
}
};
public final List<Command> getLocalList() {
List<Command> list = this.threadLocal.get();
list.clear();
return list;
}
static interface CommandCollector {
public Object getResult();
public void visit(Command command);
public void finish();
public CommandCollector reset();
}
static class KeyStringCollector implements CommandCollector {
char[] buf = new char[1024*2];
int count = 0;
boolean wasFirst = true;
public CommandCollector reset() {
this.count = 0;
this.wasFirst = true;
return this;
}
public Object getResult() {
return new String(this.buf, 0, this.count);
}
public void visit(Command command) {
if (this.wasFirst) {
this.append(command.getKey());
this.wasFirst = false;
} else {
this.append(" ");
this.append(command.getKey());
}
}
private void expandCapacity(int minimumCapacity) {
int newCapacity = (this.buf.length + 1) * 2;
if (newCapacity < 0) {
newCapacity = Integer.MAX_VALUE;
} else if (minimumCapacity > newCapacity) {
newCapacity = minimumCapacity;
}
char[] copy = new char[newCapacity];
System.arraycopy(this.buf, 0, copy, 0, Math.min(this.buf.length, newCapacity));
this.buf = copy;
}
private void append(String str) {
int len = str.length();
if (len == 0) {
return;
}
int newCount = this.count + len;
if (newCount > this.buf.length) {
this.expandCapacity(newCount);
}
str.getChars(0, len, this.buf, this.count);
this.count = newCount;
}
public void finish() {
// do nothing
}
}
private static class BinarySetQCollector implements CommandCollector {
ArrayList<IoBuffer> bufferList = new ArrayList<IoBuffer>();
int totalBytes;
BinaryStoreCommand prevCommand;
Map<Object, Command> mergeCommands;
public CommandCollector reset() {
this.bufferList.clear();
this.totalBytes = 0;
this.prevCommand = null;
this.mergeCommands = null;
return this;
}
public Object getResult() {
byte[] buf = new byte[this.totalBytes];
int offset = 0;
for (IoBuffer buffer : this.bufferList) {
byte[] ba = buffer.array();
System.arraycopy(ba, 0, buf, offset, ba.length);
offset += ba.length;
}
BinarySetMultiCommand resultCommand = new BinarySetMultiCommand(
null, CommandType.SET_MANY, new CountDownLatch(1));
resultCommand.setIoBuffer(IoBuffer.wrap(buf));
resultCommand.setMergeCommands(this.mergeCommands);
resultCommand.setMergeCount(this.mergeCommands.size());
return resultCommand;
}
public void visit(Command command) {
// Encode prev command
if (this.prevCommand != null) {
// first n-1 send setq command
BinaryStoreCommand setqCmd = new BinaryStoreCommand(
this.prevCommand.getKey(), this.prevCommand.getKeyBytes(),
CommandType.SET, null, this.prevCommand.getExpTime(),
this.prevCommand.getCas(),
// set noreply to be true
this.prevCommand.getValue(), true,
this.prevCommand.getTranscoder());
// We must set the opaque to get error message.
int opaque = OpaqueGenerater.getInstance().getNextValue();
setqCmd.setOpaque(opaque);
setqCmd.encode();
this.totalBytes += setqCmd.getIoBuffer().remaining();
this.bufferList.add(setqCmd.getIoBuffer());
// GC friendly
setqCmd.setIoBuffer(MemcachedHandler.EMPTY_BUF);
setqCmd.setValue(null);
this.prevCommand.setValue(null);
this.prevCommand.setIoBuffer(MemcachedHandler.EMPTY_BUF);
if (this.mergeCommands == null) {
this.mergeCommands = new HashMap<Object, Command>();
}
this.mergeCommands.put(opaque, this.prevCommand);
}
this.prevCommand = (BinaryStoreCommand) command;
}
public void finish() {
if (this.mergeCommands == null) {
return;
}
// prevCommand is the last command,last command must be a SET
// command,ensure
// previous SETQ commands sending response back
BinaryStoreCommand setqCmd = new BinaryStoreCommand(
this.prevCommand.getKey(), this.prevCommand.getKeyBytes(),
CommandType.SET, null, this.prevCommand.getExpTime(),
this.prevCommand.getCas(),
// set noreply to be false.
this.prevCommand.getValue(), false, this.prevCommand.getTranscoder());
// We must set the opaque to get error message.
int opaque = OpaqueGenerater.getInstance().getNextValue();
setqCmd.setOpaque(opaque);
setqCmd.encode();
this.bufferList.add(setqCmd.getIoBuffer());
this.totalBytes += setqCmd.getIoBuffer().remaining();
if (this.mergeCommands != null) {
this.mergeCommands.put(opaque, this.prevCommand);
}
}
}
private static class BinaryGetQCollector implements CommandCollector {
ArrayList<IoBuffer> bufferList = new ArrayList<IoBuffer>(50);
int totalBytes;
Command prevCommand;
public CommandCollector reset(){
this.bufferList.clear();
this.totalBytes = 0;
this.prevCommand = null;
return this;
}
public Object getResult() {
byte[] buf = new byte[this.totalBytes];
int offset = 0;
for (IoBuffer buffer : this.bufferList) {
byte[] ba = buffer.array();
System.arraycopy(ba, 0, buf, offset, ba.length);
offset += ba.length;
}
BinaryGetMultiCommand resultCommand = new BinaryGetMultiCommand(
null, CommandType.GET_MANY, new CountDownLatch(1));
resultCommand.setIoBuffer(IoBuffer.wrap(buf));
return resultCommand;
}
public void visit(Command command) {
// Encode prev command
if (this.prevCommand != null) {
// first n-1 send getq command
Command getqCommand = new BinaryGetCommand(
this.prevCommand.getKey(), this.prevCommand.getKeyBytes(), null,
null, OpCode.GET_KEY_QUIETLY, true);
getqCommand.encode();
this.totalBytes += getqCommand.getIoBuffer().remaining();
this.bufferList.add(getqCommand.getIoBuffer());
}
this.prevCommand = command;
}
public void finish() {
// prev command is the last command,last command must be getk,ensure
// getq commands sending response back
Command lastGetKCommand = new BinaryGetCommand(
this.prevCommand.getKey(), this.prevCommand.getKeyBytes(),
CommandType.GET_ONE, new CountDownLatch(1), OpCode.GET_KEY,
false);
lastGetKCommand.encode();
this.bufferList.add(lastGetKCommand.getIoBuffer());
this.totalBytes += lastGetKCommand.getIoBuffer().remaining();
}
}
@SuppressWarnings("unchecked")
private final Command mergeGetCommands(final Command currentCmd,
final Queue writeQueue, final Queue<Command> executingCmds,
CommandType expectedCommandType) {
Map<Object, Command> mergeCommands = null;
int mergeCount = 1;
final CommandCollector commandCollector = this.createGetCommandCollector();
currentCmd.setStatus(OperationStatus.WRITING);
commandCollector.visit(currentCmd);
while (mergeCount < this.mergeFactor) {
Command nextCmd = (Command) writeQueue.peek();
if (nextCmd == null) {
break;
}
if (nextCmd.isCancel()) {
writeQueue.remove();
continue;
}
if (nextCmd.getCommandType() == expectedCommandType) {
if (mergeCommands == null) { // lazy initialize
mergeCommands = new HashMap<Object, Command>(
this.mergeFactor / 2);
mergeCommands.put(currentCmd.getKey(), currentCmd);
}
if (log.isDebugEnabled()) {
log.debug("Merge get command:" + nextCmd.toString());
}
nextCmd.setStatus(OperationStatus.WRITING);
Command removedCommand = (Command) writeQueue.remove();
// If the key is exists,add the command to associated list.
if (mergeCommands.containsKey(removedCommand.getKey())) {
final AssocCommandAware mergedGetCommand = (AssocCommandAware) mergeCommands
.get(removedCommand.getKey());
if (mergedGetCommand.getAssocCommands() == null) {
mergedGetCommand
.setAssocCommands(new ArrayList<Command>(5));
}
mergedGetCommand.getAssocCommands().add(removedCommand);
} else {
commandCollector.visit(nextCmd);
mergeCommands.put(removedCommand.getKey(), removedCommand);
}
mergeCount++;
} else {
break;
}
}
if (mergeCount == 1) {
return currentCmd;
} else {
commandCollector.finish();
if (log.isDebugEnabled()) {
log.debug("Merge optimieze:merge " + mergeCount
+ " get commands");
}
return this.newMergedCommand(mergeCommands, mergeCount,
commandCollector, expectedCommandType);
}
}
private static final ThreadLocal<BinarySetQCollector> BIN_SET_CMD_COLLECTOR_THREAD_LOCAL = new ThreadLocal<Optimizer.BinarySetQCollector>(){
@Override
protected BinarySetQCollector initialValue() {
return new BinarySetQCollector();
}
};
private final Command mergeSetCommands(final Command currentCmd,
final Queue writeQueue, final Queue<Command> executingCmds,
CommandType expectedCommandType, int sendBufferSize) {
int mergeCount = 1;
final CommandCollector commandCollector = BIN_SET_CMD_COLLECTOR_THREAD_LOCAL.get().reset();
currentCmd.setStatus(OperationStatus.WRITING);
int totalBytes = currentCmd.getIoBuffer().remaining();
commandCollector.visit(currentCmd);
while (mergeCount < this.mergeFactor && totalBytes <= sendBufferSize) {
Command nextCmd = (Command) writeQueue.peek();
if (nextCmd == null) {
break;
}
if (nextCmd.isCancel()) {
writeQueue.remove();
continue;
}
if (nextCmd.getCommandType() == expectedCommandType
&& !nextCmd.isNoreply()) {
if (log.isDebugEnabled()) {
log.debug("Merge set command:" + nextCmd.toString());
}
nextCmd.setStatus(OperationStatus.WRITING);
writeQueue.remove();
commandCollector.visit(nextCmd);
mergeCount++;
} else {
break;
}
totalBytes += nextCmd.getIoBuffer().remaining();
}
if (mergeCount == 1) {
return currentCmd;
} else {
commandCollector.finish();
if (log.isDebugEnabled()) {
log.debug("Merge optimieze:merge " + mergeCount
+ " get commands");
}
return (Command) commandCollector.getResult();
}
}
private static ThreadLocal<KeyStringCollector> TEXT_GET_CMD_COLLECTOR_THREAD_LOCAL = new ThreadLocal<Optimizer.KeyStringCollector>(){
@Override
public KeyStringCollector initialValue(){
return new KeyStringCollector();
}
};
private static ThreadLocal<BinaryGetQCollector> BIN_GET_CMD_COLLECTOR_THREAD_LOCAL = new ThreadLocal<Optimizer.BinaryGetQCollector>(){
@Override
public BinaryGetQCollector initialValue(){
return new BinaryGetQCollector();
}
};
private CommandCollector createGetCommandCollector() {
switch (this.protocol) {
case Binary:
return BIN_GET_CMD_COLLECTOR_THREAD_LOCAL.get().reset();
default:
return TEXT_GET_CMD_COLLECTOR_THREAD_LOCAL.get().reset();
}
}
private Command newMergedCommand(final Map<Object, Command> mergeCommands,
int mergeCount, final CommandCollector commandCollector,
final CommandType commandType) {
if (this.protocol == Protocol.Text) {
String resultKey = (String) commandCollector.getResult();
byte[] keyBytes = ByteUtils.getBytes(resultKey);
byte[] cmdBytes = commandType == CommandType.GET_ONE ? Constants.GET
: Constants.GETS;
final byte[] buf = new byte[cmdBytes.length + 3 + keyBytes.length];
ByteUtils.setArguments(buf, 0, cmdBytes, keyBytes);
TextGetOneCommand cmd = new TextGetOneCommand(resultKey, keyBytes,
commandType, null);
cmd.setMergeCommands(mergeCommands);
cmd.setWriteFuture(new FutureImpl<Boolean>());
cmd.setMergeCount(mergeCount);
cmd.setIoBuffer(IoBuffer.wrap(buf));
return cmd;
} else {
BinaryGetMultiCommand result = (BinaryGetMultiCommand) commandCollector
.getResult();
result.setMergeCount(mergeCount);
result.setMergeCommands(mergeCommands);
return result;
}
}
}