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：

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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：

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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：

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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：

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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：

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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：

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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：

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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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1

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