如何解决Lock wait timeout exceeded的问题

这篇文章主要介绍"如何解决Lock wait timeout exceeded的问题"，在日常操作中，相信很多人在如何解决Lock wait timeout exceeded的问题问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答"如何解决Lock wait timeout exceeded的问题"的疑惑有所帮助！接下来，请跟着小编一起来学习吧！

背景

最近在排查问题时发现，偶尔会发生关于数据库锁超时的现象，会发生像如下的报错信息：

Exception in thread "pool-3-thread-1" org.springframework.dao.CannotAcquireLockException: ### Error updating database.  Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLTransactionRollbackException: Lock wait timeout exceeded; try restarting transaction### The error may involve com.zr.center.mybatis.auto.mapper.UserMapper.updateByExampleSelective-Inline### The error occurred while setting parameters### SQL: update user      SET user_name = ?                          WHERE (  user_id = ? )### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLTransactionRollbackException: Lock wait timeout exceeded; try restarting transaction; ]; Lock wait timeout exceeded; try restarting transaction; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLTransactionRollbackException: Lock wait timeout exceeded; try restarting transaction        at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:262)        at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:72)        at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75)        at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447)        at com.sun.proxy.$Proxy101.update(Unknown Source)        at org.mybatis.spring.SqlSessionTemplate.update(SqlSessionTemplate.java:295)        at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:59)        at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53)        at com.sun.proxy.$Proxy103.updateByExampleSelective(Unknown Source)        at com.zr.center.framework.web.service.BaseService.updateByExampleSelective(BaseService.java:97)        at com.zr.center.api.test.service.TestService.updateUserName(TestService.java:34)        at com.zr.center.api.test.service.TestService$$FastClassBySpringCGLIB$$bd3aa32.invoke()        at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:746)        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)        at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294)        at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98)        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)        at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688)        at com.zr.center.api.test.service.TestService$$EnhancerBySpringCGLIB$$59b19302.updateUserName()        at com.zr.center.ApplicationTests.lambda$testTxLockWaiting$0(ApplicationTests.java:32)        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)        at java.lang.Thread.run(Thread.java:745)Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLTransactionRollbackException: Lock wait timeout exceeded; try restarting transaction        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)        at java.lang.reflect.Constructor.newInstance(Constructor.java:423)        at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)        at com.mysql.jdbc.Util.getInstance(Util.java:408)        at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:952)        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3976)        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3912)        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2530)        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2683)        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2486)

排查

经过排查，DBA给出的日志中并未有死锁，死锁的原因排除，查询业务日志发现在高并发的时期有时会有重复请求过来，也有一个服务在处理某个逻辑时会发一条mq消息，而同时会消费这条消息，此时也会导致锁超时。超时原因就是因为一个事务中处理的逻辑过多，有调外部服务(超时)，有更新其它多张表的操作，这样就会导致后面事务请求超时，报以上错误。

重现步骤

• 数据库配置

关于配置信息查看，可以看到事务隔离是RR,事务锁等待时长为默认的50s

• 事务代码

/** * @description: 用户服务超时测试 * @author: chong guo * @create: 2018-12-10 14:44 */@Service@Slf4jpublic class TestService extends BaseService {    /**     * 更新用户名称     *     * @param userId     * @param name     */    @Transactional(rollbackFor = Exception.class)    public void updateUserName(Long userId, String name) throws InterruptedException {        log.info("开始更新用户名【{}】，用户ID为【{}】", name, userId);        UserExample userExample = new UserExample();        userExample.createCriteria().andUserIdEqualTo(userId);        User user = new User();        user.setUserName(name);        super.updateByExampleSelective(user, userExample);        // 模拟业务超时，有可能调用外部远程服务超时，也有可能处理其它逻辑        Thread.sleep(55000);        log.info("结束更新用户名【{}】，用户ID为【{}】", name, userId);    }}

• 模拟并发

/** * @author  Chong Guo */@RunWith(SpringRunner.class)@SpringBootTest@Slf4jpublic class ApplicationTests {    @Resource    TestService testService;    private final int threadCount = 5;    @Test    public void testTxLockWaiting() throws InterruptedException {        CountDownLatch countDownLatch = new CountDownLatch(threadCount);        ExecutorService threadPool = Executors.newFixedThreadPool(300);        for (int i = 0; i < threadCount; i++) {            threadPool.execute(() -> {                try {                    testService.updateUserName(611526166943105024L, "chongguo");                } catch (InterruptedException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                } finally {                    countDownLatch.countDown();                }            });        }        countDownLatch.await();        threadPool.shutdown();        log.info("Test tx lock is over");        Thread.sleep(100000);    }}

运行代码后会现三次失败，二次成功，失败原因都是锁超时

到此，关于"如何解决Lock wait timeout exceeded的问题"的学习就结束了，希望能够解决大家的疑惑。理论与实践的搭配能更好的帮助大家学习，快去试试吧！若想继续学习更多相关知识，请继续关注网站，小编会继续努力为大家带来更多实用的文章！