zookeeper笔记之基于zk实现分布式锁
一、分布式锁概述
Java中基于AQS框架提供了一系列的锁，但是当需要在集群中的多台机器上互斥执行一段代码或使用资源时Java提供的这种单机锁就没了用武之地，此时需要使用分布式锁协调它们。分布式锁有很多实现，基于redis、基于数据库等等，本次讨论的是基于zk实现分布式锁。
免责声明：下面的分布式锁是本人学习zk时根据其特性摸索出来的实现，并不代表业内权威做法，仅作为不同的思想碰撞出灵感的小火花之用，如有错误之处还望多多指教。
二、不可重入的分布式锁（有羊群效应，不公平锁）
首先比较容易想到的就是约定一个路径的创建作为抢占锁的条件，比如路径/zk-lock/foo，然后集群中每台机器上的程序都尝试去创建这样一个临时节点，谁创建成功了谁就抢到了锁，没有创建成功的把自己休眠，休眠之前在/zk-lock/foo节点上添加watcher，watcher中当/zk-lock/foo节点被删除时将自己叫醒重新抢占锁，一直重复这个过程直到所有线程都抢到过锁。
再来说抢到锁的机器，这台机器抢到锁之后就开始执行一些业务逻辑等乱七八糟的事情，执行完之后需要unlock释放锁，这里所谓的释放锁实际上就是将/zk-lock/foo节点删除，之前说过了其它没有抢到锁的机器都在这个节点上面添加了一个watcher，所以删除/zk-lock/foo实际上就是将其它休眠的机器唤醒让它们重新抢占锁。
上述过程流程图：
代码实现，首先是分布式锁的接口定义：
package cc11001100.zookeeper.lock; /**
* @author CC11001100
*/
public interface DistributeLock { void lock() throws InterruptedException; void unlock(); /**
* 释放此分布式锁所需要的资源，比如zookeeper连接
*/
void releaseResource(); }
按上述流程图对分布式锁的一个实现：
package cc11001100.zookeeper.lock; import cc11001100.zookeeper.utils.ZooKeeperUtil;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper; import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.UUID; /**
* 不可重入有羊群效应的分布式锁（不公平锁）
*
* @author CC11001100
*/
public class NotReentrantDistributeLockWithHerdEffect implements DistributeLock { private final Thread currentThread; private String lockBasePath;
private String lockName;
private String lockFullPath; private ZooKeeper zooKeeper;
private String myId;
private String myName; public NotReentrantDistributeLockWithHerdEffect(String lockBasePath, String lockName) throws IOException {
this.lockBasePath = lockBasePath;
this.lockName = lockName;
this.lockFullPath = this.lockBasePath + "/" + lockName;
this.zooKeeper = ZooKeeperUtil.getZooKeeper();
this.currentThread = Thread.currentThread();
this.myId = UUID.randomUUID().toString();
this.myName = Thread.currentThread().getName();
createLockBasePath();
} private void createLockBasePath() {
try {
if (zooKeeper.exists(lockBasePath, null) == null) {
zooKeeper.create(lockBasePath, "".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
}
} catch (KeeperException | InterruptedException ignored) {
}
} @Override
public void lock() throws InterruptedException {
try {
zooKeeper.create(lockFullPath, myId.getBytes(StandardCharsets.UTF_8), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL);
System.out.println(myName + ": get lock");
} catch (KeeperException.NodeExistsException e) {
// 如果节点已经存在，则监听此节点，当节点被删除时再抢占锁
try {
zooKeeper.exists(lockFullPath, event -> {
synchronized (currentThread) {
currentThread.notify();
System.out.println(myName + ": wake");
}
});
} catch (KeeperException.NoNodeException e1) {
// 间不容发之际，其它人释放了锁
lock();
} catch (KeeperException | InterruptedException e1) {
e1.printStackTrace();
}
synchronized (currentThread) {
currentThread.wait();
}
lock();
} catch (KeeperException | InterruptedException e) {
e.printStackTrace();
}
} @Override
public void unlock() {
try {
byte[] nodeBytes = zooKeeper.getData(lockFullPath, false, null);
String currentHoldLockNodeId = new String(nodeBytes, StandardCharsets.UTF_8);
// 只有当前锁的持有者是自己的时候，才能删除节点
if (myId.equalsIgnoreCase(currentHoldLockNodeId)) {
zooKeeper.delete(lockFullPath, -1);
}
} catch (KeeperException | InterruptedException e) {
e.printStackTrace();
}
System.out.println(myName + ": releaseResource lock");
} @Override
public void releaseResource() {
try {
// 将zookeeper连接释放掉
zooKeeper.close();
} catch (InterruptedException e) {
e.printStackTrace();
}
} }
测试代码如下：
package cc11001100.zookeeper.lock; import java.io.IOException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.concurrent.TimeUnit; /**
* @author CC11001100
*/
public class NotReentrantDistributeLockWithHerdEffectTest { private static String now() {
return LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
} public static void main(String[] args) {
int nodeNum = 10;
for (int i = 0; i < nodeNum; i++) {
new Thread(() -> {
DistributeLock lock = null;
try {
lock = new NotReentrantDistributeLockWithHerdEffect("/zk-lock", "foo");
lock.lock();
String myName = Thread.currentThread().getName();
System.out.println(myName + ": hold lock, now=" + now());
TimeUnit.SECONDS.sleep(3);
lock.unlock();
} catch (IOException | InterruptedException e) {
e.printStackTrace();
} finally {
if (lock != null) {
lock.releaseResource();
}
}
}, "thread-name-" + i).start();
} // output:
// thread-name-8: get lock
// thread-name-8: hold lock, now=2019-01-14 13:31:48
// thread-name-8: releaseResource lock
// thread-name-2: wake
// thread-name-5: wake
// thread-name-3: wake
// thread-name-1: wake
// thread-name-4: wake
// thread-name-9: wake
// thread-name-0: wake
// thread-name-7: wake
// thread-name-6: wake
// thread-name-2: get lock
// thread-name-2: hold lock, now=2019-01-14 13:31:51
// thread-name-7: wake
// thread-name-2: releaseResource lock
// thread-name-6: wake
// thread-name-0: wake
// thread-name-9: wake
// thread-name-1: wake
// thread-name-3: wake
// thread-name-5: wake
// thread-name-4: wake
// thread-name-0: get lock
// thread-name-0: hold lock, now=2019-01-14 13:31:54
// thread-name-6: wake
// thread-name-1: wake
// thread-name-7: wake
// thread-name-4: wake
// thread-name-3: wake
// thread-name-5: wake
// thread-name-0: releaseResource lock
// thread-name-9: wake
// thread-name-1: get lock
// thread-name-1: hold lock, now=2019-01-14 13:31:57
// thread-name-9: wake
// thread-name-6: wake
// thread-name-7: wake
// thread-name-3: wake
// thread-name-5: wake
// thread-name-4: wake
// thread-name-1: releaseResource lock
// thread-name-9: get lock
// thread-name-9: hold lock, now=2019-01-14 13:32:00
// thread-name-7: wake
// thread-name-4: wake
// thread-name-5: wake
// thread-name-3: wake
// thread-name-9: releaseResource lock
// thread-name-6: wake
// thread-name-3: get lock
// thread-name-3: hold lock, now=2019-01-14 13:32:03
// thread-name-6: wake
// thread-name-5: wake
// thread-name-4: wake
// thread-name-3: releaseResource lock
// thread-name-7: wake
// thread-name-6: get lock
// thread-name-6: hold lock, now=2019-01-14 13:32:06
// thread-name-7: wake
// thread-name-6: releaseResource lock
// thread-name-4: wake
// thread-name-5: wake
// thread-name-7: get lock
// thread-name-7: hold lock, now=2019-01-14 13:32:09
// thread-name-4: wake
// thread-name-7: releaseResource lock
// thread-name-5: wake
// thread-name-5: get lock
// thread-name-5: hold lock, now=2019-01-14 13:32:12
// thread-name-5: releaseResource lock
// thread-name-4: wake
// thread-name-4: get lock
// thread-name-4: hold lock, now=2019-01-14 13:32:15
// thread-name-4: releaseResource lock } }
三、不可重入的分布式锁（无羊群效应，公平锁）
上面实现的代码虽然实现了基本的锁的功能，但是它有一个比较致命的问题，就是当释放锁的时候会把其它所有机器全部唤醒，但是最终只有一台机器会抢到锁，没抢到的还得继续休眠，尤其是当机器数比较多的时候，叫醒了好几十台机器，结果还是只有一台机器能够抢到锁（堪比12306的抢票难度...），但是不公平锁就是这样啊，需要大家一起抢，否则怎么能体现出不公平呢，这个现象被称为羊群效应。
其实这个问题可以变通一下，参考Java中AQS框架的CLH队列的实现，我们可以让其排队，每台机器来抢锁的时候都要排队，排队的时候领一个号码称为自己的ticket，这个ticket是有序的，每次增加1，所以只需要前面的人释放锁的时候叫醒后面的第一个人就可以了，即每台机器在领完号码的时候都往自己前面的机器的ticket上添加一个watcher，当前面的执行完业务逻辑释放锁的时候将自己叫醒，当前面没有人的时候说明已经轮到了自己，即直接获得了锁，关于获取前面一个人的ticket，因为ticket是每次递增1的，所以完全可以通过自己的ticket计算出前面一个人的ticket，没必须要非获取父节点下的所有children。然后就是号码的发放，使用zookeeper的顺序临时节点可以保证每次发放的号码都是有序的，同时当持有锁的机器意外挂掉的时候能够自动释放锁。
上述过程流程图：
代码实现：
package cc11001100.zookeeper.lock; import cc11001100.zookeeper.utils.ZooKeeperUtil;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat; import java.io.IOException; /**
* 不可重入没有羊群效应的锁（公平锁）
*
* @author CC11001100
*/
public class NotReentrantDistributeLock implements DistributeLock { private final Thread currentThread; private String lockBasePath;
private String lockPrefix;
private String lockFullPath; private ZooKeeper zooKeeper;
private String myName;
private int myTicket; public NotReentrantDistributeLock(String lockBasePath, String lockPrefix) throws IOException {
this.lockBasePath = lockBasePath;
this.lockPrefix = lockPrefix;
this.lockFullPath = lockBasePath + "/" + lockPrefix;
this.zooKeeper = ZooKeeperUtil.getZooKeeper();
this.currentThread = Thread.currentThread();
this.myName = currentThread.getName();
createLockBasePath();
} private void createLockBasePath() {
try {
if (zooKeeper.exists(lockBasePath, null) == null) {
zooKeeper.create(lockBasePath, "".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
}
} catch (KeeperException | InterruptedException ignored) {
}
} @Override
public void lock() throws InterruptedException {
log("begin get lock");
try {
String path = zooKeeper.create(lockFullPath, "".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL);
myTicket = extractMyTicket(path);
String previousNode = buildPath(myTicket - 1);
Stat exists = zooKeeper.exists(previousNode, event -> {
synchronized (currentThread) {
currentThread.notify();
log("wake");
}
});
if (exists != null) {
synchronized (currentThread) {
currentThread.wait();
}
}
log("get lock success");
} catch (KeeperException e) {
e.printStackTrace();
}
} private int extractMyTicket(String path) {
int splitIndex = path.lastIndexOf("/");
return Integer.parseInt(path.substring(splitIndex + 1).replace(lockPrefix, ""));
} private String buildPath(int ticket) {
return String.format("%s%010d", lockFullPath, ticket);
} @Override
public void unlock() {
log("begin release lock");
try {
zooKeeper.delete(buildPath(myTicket), -1);
} catch (KeeperException | InterruptedException e) {
e.printStackTrace();
}
log("end release lock");
} @Override
public void releaseResource() {
try {
// 将zookeeper连接释放掉
zooKeeper.close();
} catch (InterruptedException e) {
e.printStackTrace();
}
} private void log(String msg) {
System.out.printf("[%d] %s : %s\n", myTicket, myName, msg);
} }
测试代码：
package cc11001100.zookeeper.lock; import java.io.IOException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.concurrent.TimeUnit; /**
* @author CC11001100
*/
public class NotReentrantDistributeLockTest { private static String now() {
return LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
} public static void main(String[] args) { int nodeNum = 10;
for (int i = 0; i < nodeNum; i++) {
new Thread(() -> {
DistributeLock lock = null;
try {
lock = new NotReentrantDistributeLock("/zk-lock", "bar");
lock.lock();
String myName = Thread.currentThread().getName();
System.out.println(myName + ": get lock success, now=" + now());
TimeUnit.SECONDS.sleep(3);
lock.unlock();
} catch (IOException | InterruptedException e) {
e.printStackTrace();
} finally {
if (lock != null) {
lock.releaseResource();
}
}
}, "thread-name-" + i).start();
} // output:
// [0] thread-name-6 : begin get lock
// [0] thread-name-3 : begin get lock
// [0] thread-name-5 : begin get lock
// [0] thread-name-4 : begin get lock
// [0] thread-name-8 : begin get lock
// [0] thread-name-9 : begin get lock
// [0] thread-name-2 : begin get lock
// [0] thread-name-7 : begin get lock
// [0] thread-name-1 : begin get lock
// [0] thread-name-0 : begin get lock
// [170] thread-name-1 : get lock success
// thread-name-1: get lock success, now=2019-01-14 17:59:56
// [170] thread-name-1 : begin release lock
// [170] thread-name-1 : end release lock
// [171] thread-name-9 : wake
// [171] thread-name-9 : get lock success
// thread-name-9: get lock success, now=2019-01-14 17:59:59
// [171] thread-name-9 : begin release lock
// [171] thread-name-9 : end release lock
// [172] thread-name-4 : wake
// [172] thread-name-4 : get lock success
// thread-name-4: get lock success, now=2019-01-14 18:00:02
// [172] thread-name-4 : begin release lock
// [173] thread-name-0 : wake
// [172] thread-name-4 : end release lock
// [173] thread-name-0 : get lock success
// thread-name-0: get lock success, now=2019-01-14 18:00:05
// [173] thread-name-0 : begin release lock
// [174] thread-name-6 : wake
// [173] thread-name-0 : end release lock
// [174] thread-name-6 : get lock success
// thread-name-6: get lock success, now=2019-01-14 18:00:08
// [174] thread-name-6 : begin release lock
// [175] thread-name-7 : wake
// [174] thread-name-6 : end release lock
// [175] thread-name-7 : get lock success
// thread-name-7: get lock success, now=2019-01-14 18:00:11
// [175] thread-name-7 : begin release lock
// [176] thread-name-3 : wake
// [175] thread-name-7 : end release lock
// [176] thread-name-3 : get lock success
// thread-name-3: get lock success, now=2019-01-14 18:00:14
// [176] thread-name-3 : begin release lock
// [177] thread-name-8 : wake
// [176] thread-name-3 : end release lock
// [177] thread-name-8 : get lock success
// thread-name-8: get lock success, now=2019-01-14 18:00:17
// [177] thread-name-8 : begin release lock
// [178] thread-name-2 : wake
// [177] thread-name-8 : end release lock
// [178] thread-name-2 : get lock success
// thread-name-2: get lock success, now=2019-01-14 18:00:20
// [178] thread-name-2 : begin release lock
// [179] thread-name-5 : wake
// [178] thread-name-2 : end release lock
// [179] thread-name-5 : get lock success
// thread-name-5: get lock success, now=2019-01-14 18:00:23
// [179] thread-name-5 : begin release lock
// [179] thread-name-5 : end release lock } }
四、可重入的分布式锁（无羊群效应，公平锁）
我们的锁实现得越来越好了，但是它还有一个比较致命的问题，就是它不能重入，所谓的重入就是递归获取锁，当已经持有锁时再尝试获取锁时，可重入锁会直接获取成功，同时将重入次数加1，当释放锁时，将重入次数减1，只有当重入次数为0时才彻底释放掉锁。而上面的锁属于不可重入锁，当尝试递归获取锁时会产生死锁永远等待下去，这很明显是不合理的，这一小节就讨论一下如何将上一节的不可重入锁转换为重入锁。
其实我的想法很简单，首先能够确定的是肯定需要在哪里保存锁的重入次数，因为已经获得了锁的机器的重入次数并不需要让其它机器知道，其它机器只要知道现在锁在这哥们手里攥着就可以了，所以可以简单的将重入次数作为DistributeLock的一个成员变量，比如叫做reentrantCount，每次尝试获取锁的时候先判断这个变量是否不为0，如果不为0的话说明当前机器已经获得了锁，根据重入锁的特性，直接将重入次数加1即可，只有当reentrantCount为0的时候才需要去排队等待获取锁。还有释放锁的时候也是判断当前reentrantCount的值，如果这个值不为0的话说明当前还是在递归嵌套中，直接将reentrantCount减1即可，然后判断reentrantCount的值如果为0的话说明锁的所有重入都已经释放掉了，直接将当前锁的ticket删除，因为队列中的后一台机器已经在当前的ticket上添加了watcher，所以删除当前ticket的动作相当于叫醒下一个排队的人。
上述过程流程图：
代码实现：
package cc11001100.zookeeper.lock; import cc11001100.zookeeper.utils.ZooKeeperUtil;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat; import java.io.IOException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter; /**
* 可重入无羊群效应的分布式锁（公平锁）
*
* @author CC11001100
*/
public class ReentrantDistributeLock implements DistributeLock { private final Thread currentThread; private String lockBasePath;
private String lockPrefix;
private String lockFullPath; private ZooKeeper zooKeeper;
private String myName;
private int myTicket; // 使用一个本机变量记载重复次数，这个值就不存储在zookeeper上了，
// 一则修改zk节点值还需要网络会慢一些，二是其它节点只需要知道有个节点当前持有锁就可以了，至于重入几次不关它们的事呀
private int reentrantCount = 0; public ReentrantDistributeLock(String lockBasePath, String lockName) throws IOException {
this.lockBasePath = lockBasePath;
this.lockPrefix = lockName;
this.lockFullPath = lockBasePath + "/" + lockName;
this.zooKeeper = ZooKeeperUtil.getZooKeeper();
this.currentThread = Thread.currentThread();
this.myName = currentThread.getName();
createLockBasePath();
} private void createLockBasePath() {
try {
if (zooKeeper.exists(lockBasePath, null) == null) {
zooKeeper.create(lockBasePath, "".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
}
} catch (KeeperException | InterruptedException ignored) {
}
} @Override
public void lock() throws InterruptedException {
log("begin get lock"); // 如果reentrantCount不为0说明当前节点已经持有锁了，无需等待，直接增加重入次数即可
if (reentrantCount != 0) {
reentrantCount++;
log("get lock success");
return;
} // 说明还没有获取到锁，需要设置watcher监听上一个节点释放锁事件
try {
String path = zooKeeper.create(lockFullPath, "".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL);
myTicket = extractMyTicket(path);
String previousNode = buildPathByTicket(myTicket - 1);
Stat exists = zooKeeper.exists(previousNode, event -> {
synchronized (currentThread) {
currentThread.notify();
log("wake");
}
});
if (exists != null) {
synchronized (currentThread) {
currentThread.wait();
}
}
reentrantCount++;
log("get lock success");
} catch (KeeperException e) {
e.printStackTrace();
}
} private int extractMyTicket(String path) {
int splitIndex = path.lastIndexOf("/");
return Integer.parseInt(path.substring(splitIndex + 1).replace(lockPrefix, ""));
} private String buildPathByTicket(int ticket) {
return String.format("%s%010d", lockFullPath, ticket);
} @Override
public void unlock() {
log("begin release lock"); // 每次unlock的时候将递归次数减1，没有减到0说明还在递归中
reentrantCount--;
if (reentrantCount != 0) {
log("end release lock");
return;
} // 只有当重入次数为0的时候才删除节点，将锁释放掉
try {
zooKeeper.delete(buildPathByTicket(myTicket), -1);
} catch (KeeperException | InterruptedException e) {
e.printStackTrace();
}
log("end release lock");
} @Override
public void releaseResource() {
try {
// 将zookeeper连接释放掉
zooKeeper.close();
} catch (InterruptedException e) {
e.printStackTrace();
}
} private void log(String msg) {
System.out.printf("[%s], ticket=%d, reentrantCount=%d, threadName=%s, msg=%s\n", now(), myTicket, reentrantCount, myName, msg);
} private String now() {
return LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
} }
测试代码：
package cc11001100.zookeeper.lock; import java.io.IOException;
import java.util.Random;
import java.util.concurrent.TimeUnit; /**
* 测试分布式可重入锁，每个锁随机重入，看是否会发生错误
*
* @author CC11001100
*/
public class ReentrantDistributeLockTest { public static void main(String[] args) { int nodeNum = 10;
for (int i = 0; i < nodeNum; i++) {
new Thread(() -> {
DistributeLock lock = null;
try {
lock = new ReentrantDistributeLock("/zk-lock", "bar");
lock.lock();
TimeUnit.SECONDS.sleep(1); int reentrantTimes = new Random().nextInt(10);
int reentrantCount = 0;
for (int j = 0; j < reentrantTimes; j++) {
lock.lock();
reentrantCount++;
if (Math.random() < 0.5) {
lock.unlock();
reentrantCount--;
}
}
while (reentrantCount-- > 0) {
lock.unlock();
} lock.unlock();
} catch (IOException | InterruptedException e) {
e.printStackTrace();
} finally {
if (lock != null) {
lock.releaseResource();
}
}
}, "thread-name-" + i).start();
} // output:
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-4, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-5, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-8, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-0, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-6, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-1, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-9, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-3, msg=begin get lock
// [2019-01-14 17:57:43], ticket=0, reentrantCount=0, threadName=thread-name-2, msg=begin get lock
// [2019-01-14 17:57:43], ticket=160, reentrantCount=1, threadName=thread-name-0, msg=get lock success
// [2019-01-14 17:57:44], ticket=160, reentrantCount=1, threadName=thread-name-0, msg=begin get lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=get lock success
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=begin release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=1, threadName=thread-name-0, msg=end release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=1, threadName=thread-name-0, msg=begin get lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=get lock success
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=begin get lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=3, threadName=thread-name-0, msg=get lock success
// [2019-01-14 17:57:44], ticket=160, reentrantCount=3, threadName=thread-name-0, msg=begin release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=end release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=begin get lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=3, threadName=thread-name-0, msg=get lock success
// [2019-01-14 17:57:44], ticket=160, reentrantCount=3, threadName=thread-name-0, msg=begin release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=end release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=2, threadName=thread-name-0, msg=begin release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=1, threadName=thread-name-0, msg=end release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=1, threadName=thread-name-0, msg=begin release lock
// [2019-01-14 17:57:44], ticket=160, reentrantCount=0, threadName=thread-name-0, msg=end release lock
// [2019-01-14 17:57:44], ticket=161, reentrantCount=0, threadName=thread-name-6, msg=wake
// [2019-01-14 17:57:44], ticket=161, reentrantCount=1, threadName=thread-name-6, msg=get lock success
// [2019-01-14 17:57:45], ticket=161, reentrantCount=1, threadName=thread-name-6, msg=begin get lock
// [2019-01-14 17:57:45], ticket=161, reentrantCount=2, threadName=thread-name-6, msg=get lock success
// [2019-01-14 17:57:45], ticket=161, reentrantCount=2, threadName=thread-name-6, msg=begin get lock
// [2019-01-14 17:57:45], ticket=161, reentrantCount=3, threadName=thread-name-6, msg=get lock success
// [2019-01-14 17:57:45], ticket=161, reentrantCount=3, threadName=thread-name-6, msg=begin release lock
// [2019-01-14 17:57:45], ticket=161, reentrantCount=2, threadName=thread-name-6, msg=end release lock
// [2019-01-14 17:57:45], ticket=161, reentrantCount=2, threadName=thread-name-6, msg=begin release lock
// [2019-01-14 17:57:45], ticket=161, reentrantCount=1, threadName=thread-name-6, msg=end release lock
// [2019-01-14 17:57:45], ticket=161, reentrantCount=1, threadName=thread-name-6, msg=begin release lock
// [2019-01-14 17:57:45], ticket=162, reentrantCount=0, threadName=thread-name-5, msg=wake
// [2019-01-14 17:57:45], ticket=161, reentrantCount=0, threadName=thread-name-6, msg=end release lock
// [2019-01-14 17:57:45], ticket=162, reentrantCount=1, threadName=thread-name-5, msg=get lock success
// [2019-01-14 17:57:46], ticket=162, reentrantCount=1, threadName=thread-name-5, msg=begin release lock
// [2019-01-14 17:57:46], ticket=162, reentrantCount=0, threadName=thread-name-5, msg=end release lock
// [2019-01-14 17:57:46], ticket=163, reentrantCount=0, threadName=thread-name-8, msg=wake
// [2019-01-14 17:57:46], ticket=163, reentrantCount=1, threadName=thread-name-8, msg=get lock success
// [2019-01-14 17:57:47], ticket=163, reentrantCount=1, threadName=thread-name-8, msg=begin get lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=2, threadName=thread-name-8, msg=get lock success
// [2019-01-14 17:57:47], ticket=163, reentrantCount=2, threadName=thread-name-8, msg=begin release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=1, threadName=thread-name-8, msg=end release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=1, threadName=thread-name-8, msg=begin get lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=2, threadName=thread-name-8, msg=get lock success
// [2019-01-14 17:57:47], ticket=163, reentrantCount=2, threadName=thread-name-8, msg=begin get lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=3, threadName=thread-name-8, msg=get lock success
// [2019-01-14 17:57:47], ticket=163, reentrantCount=3, threadName=thread-name-8, msg=begin get lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=4, threadName=thread-name-8, msg=get lock success
// [2019-01-14 17:57:47], ticket=163, reentrantCount=4, threadName=thread-name-8, msg=begin get lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=5, threadName=thread-name-8, msg=get lock success
// [2019-01-14 17:57:47], ticket=163, reentrantCount=5, threadName=thread-name-8, msg=begin release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=4, threadName=thread-name-8, msg=end release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=4, threadName=thread-name-8, msg=begin release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=3, threadName=thread-name-8, msg=end release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=3, threadName=thread-name-8, msg=begin release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=2, threadName=thread-name-8, msg=end release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=2, threadName=thread-name-8, msg=begin release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=1, threadName=thread-name-8, msg=end release lock
// [2019-01-14 17:57:47], ticket=163, reentrantCount=1, threadName=thread-name-8, msg=begin release lock
// [2019-01-14 17:57:47], ticket=164, reentrantCount=0, threadName=thread-name-2, msg=wake
// [2019-01-14 17:57:47], ticket=163, reentrantCount=0, threadName=thread-name-8, msg=end release lock
// [2019-01-14 17:57:47], ticket=164, reentrantCount=1, threadName=thread-name-2, msg=get lock success
// [2019-01-14 17:57:48], ticket=164, reentrantCount=1, threadName=thread-name-2, msg=begin release lock
// [2019-01-14 17:57:48], ticket=165, reentrantCount=0, threadName=thread-name-9, msg=wake
// [2019-01-14 17:57:48], ticket=164, reentrantCount=0, threadName=thread-name-2, msg=end release lock
// [2019-01-14 17:57:48], ticket=165, reentrantCount=1, threadName=thread-name-9, msg=get lock success
// [2019-01-14 17:57:49], ticket=165, reentrantCount=1, threadName=thread-name-9, msg=begin get lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=2, threadName=thread-name-9, msg=get lock success
// [2019-01-14 17:57:49], ticket=165, reentrantCount=2, threadName=thread-name-9, msg=begin release lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=1, threadName=thread-name-9, msg=end release lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=1, threadName=thread-name-9, msg=begin get lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=2, threadName=thread-name-9, msg=get lock success
// [2019-01-14 17:57:49], ticket=165, reentrantCount=2, threadName=thread-name-9, msg=begin get lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=3, threadName=thread-name-9, msg=get lock success
// [2019-01-14 17:57:49], ticket=165, reentrantCount=3, threadName=thread-name-9, msg=begin release lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=2, threadName=thread-name-9, msg=end release lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=2, threadName=thread-name-9, msg=begin release lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=1, threadName=thread-name-9, msg=end release lock
// [2019-01-14 17:57:49], ticket=165, reentrantCount=1, threadName=thread-name-9, msg=begin release lock
// [2019-01-14 17:57:49], ticket=166, reentrantCount=0, threadName=thread-name-1, msg=wake
// [2019-01-14 17:57:49], ticket=165, reentrantCount=0, threadName=thread-name-9, msg=end release lock
// [2019-01-14 17:57:49], ticket=166, reentrantCount=1, threadName=thread-name-1, msg=get lock success
// [2019-01-14 17:57:50], ticket=166, reentrantCount=1, threadName=thread-name-1, msg=begin release lock
// [2019-01-14 17:57:50], ticket=167, reentrantCount=0, threadName=thread-name-4, msg=wake
// [2019-01-14 17:57:50], ticket=166, reentrantCount=0, threadName=thread-name-1, msg=end release lock
// [2019-01-14 17:57:50], ticket=167, reentrantCount=1, threadName=thread-name-4, msg=get lock success
// [2019-01-14 17:57:51], ticket=167, reentrantCount=1, threadName=thread-name-4, msg=begin get lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=2, threadName=thread-name-4, msg=get lock success
// [2019-01-14 17:57:51], ticket=167, reentrantCount=2, threadName=thread-name-4, msg=begin release lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=1, threadName=thread-name-4, msg=end release lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=1, threadName=thread-name-4, msg=begin get lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=2, threadName=thread-name-4, msg=get lock success
// [2019-01-14 17:57:51], ticket=167, reentrantCount=2, threadName=thread-name-4, msg=begin get lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=3, threadName=thread-name-4, msg=get lock success
// [2019-01-14 17:57:51], ticket=167, reentrantCount=3, threadName=thread-name-4, msg=begin release lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=2, threadName=thread-name-4, msg=end release lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=2, threadName=thread-name-4, msg=begin release lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=1, threadName=thread-name-4, msg=end release lock
// [2019-01-14 17:57:51], ticket=167, reentrantCount=1, threadName=thread-name-4, msg=begin release lock
// [2019-01-14 17:57:51], ticket=168, reentrantCount=0, threadName=thread-name-3, msg=wake
// [2019-01-14 17:57:51], ticket=167, reentrantCount=0, threadName=thread-name-4, msg=end release lock
// [2019-01-14 17:57:51], ticket=168, reentrantCount=1, threadName=thread-name-3, msg=get lock success
// [2019-01-14 17:57:52], ticket=168, reentrantCount=1, threadName=thread-name-3, msg=begin get lock
// [2019-01-14 17:57:52], ticket=168, reentrantCount=2, threadName=thread-name-3, msg=get lock success
// [2019-01-14 17:57:52], ticket=168, reentrantCount=2, threadName=thread-name-3, msg=begin get lock
// [2019-01-14 17:57:52], ticket=168, reentrantCount=3, threadName=thread-name-3, msg=get lock success
// [2019-01-14 17:57:52], ticket=168, reentrantCount=3, threadName=thread-name-3, msg=begin release lock
// [2019-01-14 17:57:52], ticket=168, reentrantCount=2, threadName=thread-name-3, msg=end release lock
// [2019-01-14 17:57:52], ticket=168, reentrantCount=2, threadName=thread-name-3, msg=begin release lock
// [2019-01-14 17:57:52], ticket=168, reentrantCount=1, threadName=thread-name-3, msg=end release lock
// [2019-01-14 17:57:52], ticket=168, reentrantCount=1, threadName=thread-name-3, msg=begin release lock
// [2019-01-14 17:57:52], ticket=169, reentrantCount=0, threadName=thread-name-7, msg=wake
// [2019-01-14 17:57:52], ticket=168, reentrantCount=0, threadName=thread-name-3, msg=end release lock
// [2019-01-14 17:57:52], ticket=169, reentrantCount=1, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=1, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=2, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=2, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=2, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=2, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=5, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=5, threadName=thread-name-7, msg=begin get lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=6, threadName=thread-name-7, msg=get lock success
// [2019-01-14 17:57:53], ticket=169, reentrantCount=6, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=5, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=5, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=4, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=3, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=2, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=2, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=1, threadName=thread-name-7, msg=end release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=1, threadName=thread-name-7, msg=begin release lock
// [2019-01-14 17:57:53], ticket=169, reentrantCount=0, threadName=thread-name-7, msg=end release lock } }
.
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