mysql无法执行某些语句,并自动断开服务连接问题

本文记录了一个关于在使用Hibernate更新数据库及完成Activiti流程任务时遇到的MySQL通讯链接失败问题。该问题表现为在执行特定操作时抛出异常,并详细展示了错误堆栈跟踪。通过更换MySQL版本最终解决了这一难题。

存在了2天小问题终于解决

出现场景:

1. hibernate执行update语句的时候,出现这个错误,save和query没有任何问题;

2.  执行activity的processEngine.getTaskService().complete(taskId)方法时,抛出这个异常.


错误提示:

org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 2,743 milliseconds ago.  The last packet sent successfully to the server was 2,743 milliseconds ago.
### The error may exist in org/activiti/db/mapping/entity/HistoricActivityInstance.xml
### The error may involve org.activiti.engine.impl.persistence.entity.HistoricActivityInstanceEntity.selectHistoricActivityInstancesByQueryCriteria-Inline
### The error occurred while setting parameters
### SQL: select RES.*            from ACT_HI_ACTINST RES      WHERE  RES.EXECUTION_ID_ = ?                              and RES.ACT_ID_ = ?                                            and RES.END_TIME_ is null           order by RES.ID_ asc      LIMIT ? OFFSET ?
### Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 2,743 milliseconds ago.  The last packet sent successfully to the server was 2,743 milliseconds ago.
	at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:23)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:107)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:98)
	at org.activiti.engine.impl.db.DbSqlSession.selectListWithRawParameter(DbSqlSession.java:284)
	at org.activiti.engine.impl.db.DbSqlSession.selectList(DbSqlSession.java:275)
	at org.activiti.engine.impl.db.DbSqlSession.selectList(DbSqlSession.java:265)
	at org.activiti.engine.impl.persistence.entity.HistoricActivityInstanceEntityManager.findHistoricActivityInstancesByQueryCriteria(HistoricActivityInstanceEntityManager.java:56)
	at org.activiti.engine.impl.HistoricActivityInstanceQueryImpl.executeList(HistoricActivityInstanceQueryImpl.java:64)
	at org.activiti.engine.impl.AbstractQuery.listPage(AbstractQuery.java:126)
	at org.activiti.engine.impl.history.HistoryManager.findActivityInstance(HistoryManager.java:240)
	at org.activiti.engine.impl.history.HistoryManager.recordActivityEnd(HistoryManager.java:187)
	at org.activiti.engine.impl.history.handler.ActivityInstanceEndHandler.notify(ActivityInstanceEndHandler.java:28)
	at org.activiti.engine.impl.pvm.runtime.AbstractEventAtomicOperation.execute(AbstractEventAtomicOperation.java:42)
	at org.activiti.engine.impl.interceptor.CommandContext.performOperation(CommandContext.java:87)
	at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperationSync(ExecutionEntity.java:532)
	at org.activiti.engine.impl.persistence.entity.ExecutionEntity.performOperation(ExecutionEntity.java:527)
	at org.activiti.engine.impl.persistence.entity.ExecutionEntity.take(ExecutionEntity.java:367)
	at org.activiti.engine.impl.bpmn.behavior.BpmnActivityBehavior.performOutgoingBehavior(BpmnActivityBehavior.java:105)
	at org.activiti.engine.impl.bpmn.behavior.BpmnActivityBehavior.performDefaultOutgoingBehavior(BpmnActivityBehavior.java:54)
	at org.activiti.engine.impl.bpmn.behavior.FlowNodeActivityBehavior.leave(FlowNodeActivityBehavior.java:44)
	at org.activiti.engine.impl.bpmn.behavior.AbstractBpmnActivityBehavior.leave(AbstractBpmnActivityBehavior.java:47)
	at org.activiti.engine.impl.bpmn.behavior.UserTaskActivityBehavior.signal(UserTaskActivityBehavior.java:96)
	at org.activiti.engine.impl.persistence.entity.ExecutionEntity.signal(ExecutionEntity.java:350)
	at org.activiti.engine.impl.persistence.entity.TaskEntity.complete(TaskEntity.java:160)
	at org.activiti.engine.impl.cmd.CompleteTaskCmd.execute(CompleteTaskCmd.java:39)
	at org.activiti.engine.impl.cmd.CompleteTaskCmd.execute(CompleteTaskCmd.java:24)
	at org.activiti.engine.impl.cmd.NeedsActiveTaskCmd.execute(NeedsActiveTaskCmd.java:61)
	at org.activiti.engine.impl.interceptor.CommandExecutorImpl.execute(CommandExecutorImpl.java:24)
	at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:61)
	at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:31)
	at org.activiti.engine.impl.TaskServiceImpl.complete(TaskServiceImpl.java:163)
	at com.whir.a_hellworld.HelloWorld.compeleteMyPersonalTask(HelloWorld.java:84)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 2,743 milliseconds ago.  The last packet sent successfully to the server was 2,743 milliseconds ago.
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
	at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3670)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3559)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4110)
	at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
	at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
	at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2815)
	at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
	at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1379)
	at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:56)
	at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:70)
	at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:57)
	at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:259)
	at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:132)
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:105)
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:104)
	... 53 more
Caused by: java.net.SocketException: Connection reset
	at java.net.SocketInputStream.read(SocketInputStream.java:196)
	at java.net.SocketInputStream.read(SocketInputStream.java:122)
	at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:114)
	at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:161)
	at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:189)
	at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3116)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3570)
	... 68 more


本人的解决方案:

更换mysql版本......


若此方法行不通

其它解决方法:请自行百度

<think>嗯,用户的问题是查找使用HikariCP避免MySQL连接8小时自动断开的解决方案。结合用户提供的引用内容来看,核心问题在于MySQL服务端的wait_timeout参数(默认8小时)会自动关闭闲置连接,而连接池未正确处理这个机制会导致连接失效。 用户引用的资料[3]明确指出了HikariCP的关键配置缺失问题,特别是maxLifetime参数。这与我掌握的知识一致:连接池需要主动回收连接而非依赖数据库回收。引用[4]补充了MySQL断开闲置连接的机制,引用[2]则给出了具体配置示例。 用户可能正在遭遇生产环境连接失效的故障,语气中透着急切。需要给出即插即用的配置方案,同时解释原理避免后续误用。考虑到用户能提供完整的引用编号,应该是有一定技术背景的运维或开发人员。 最关键的三个配置参数: - maxLifetime必须短于wait_timeout(建议2/3),这样连接池会主动回收连接而非等MySQL回收 - idleTimeout需要设置来清理空闲连接 - keepaliveTime作为主动保活机制 额外注意点: - 连接测试query必须设置且高效(如SELECT 1) - 最小空闲连接数(minIdle)不宜过大,避免维持过多无效连接 - 生命周期需留有余量防止边界问题 用户引用[5]提到云原生环境的管理建议,虽然当前问题不直接相关,但可以作为延伸知识补充,体现解决方案的扩展性。 最后生成的问题要覆盖配置原理(为什么maxLifetime是核心)、运维场景(不同流量模式下的配置调整)和故障排查(连接泄漏检测),形成完整知识链。 </think>使用 HikariCP 避免 MySQL 连接因 8 小时闲置自动断开的核心解决方案是**配置合理的连接生命周期和保活机制**。关键配置如下(结合引用内容解析): --- ### 核心配置方案 [^2][^3][^4] 1. **`maxLifetime`(连接最大生命周期)** - **原理**:MySQL 服务端默认 `wait_timeout=28800秒(8小时)` 会强制关闭闲置连接。需将 `maxLifetime` 设置为 **短于 `wait_timeout` 的值**(建议 5-7 小时),使 HikariCP 主动回收连接而非等待 MySQL 关闭。 - **配置示例**: ```yaml hikari: max-lifetime: 1800000 # 30分钟(单位:毫秒,需根据实际 wait_timeout 调整) ``` 2. **`idleTimeout`(空闲连接超时)** - **作用**:释放长时间闲置的连接,避免连接泄漏[^1][^4]。 - **配置示例**: ```yaml hikari: idle-timeout: 600000 # 10分钟(短于 max-lifetime) ``` 3. **`keepaliveTime`(连接保活心跳)** - **原理**:定期发送测试查询维持连接活跃,防止 MySQL 因闲置断开[^3][^5]。 - **配置示例**: ```yaml hikari: keepalive-time: 30000 # 30秒发送一次心跳 ``` 4. **`connection-test-query`(连接测试语句)** - **必要性**:验证连接有效性,配合保活机制使用[^2][^3]。 - **配置示例**: ```yaml hikari: connection-test-query: SELECT 1 # 简单高效的测试语句 ``` --- ### 完整配置参考(基于引用[2][^2]优化) ```yaml spring: datasource: hikari: maximum-pool-size: 10 minimum-idle: 5 max-lifetime: 21000000 # 约 5.8 小时(短于 MySQL 的 8 小时) idle-timeout: 600000 # 10 分钟释放闲置连接 keepalive-time: 30000 # 30 秒一次心跳保活 connection-timeout: 30000 connection-test-query: SELECT 1 # 测试连接有效性 ``` --- ### 为什么能解决问题? 1. **主动回收替代被动断开** `max-lifetime < wait_timeout` 确保 HikariCP 在 MySQL 关闭连接前主动回收重建连接,避免应用使用失效连接[^3][^4]。 2. **心跳保活维持活跃** `keepaliveTime` 定期发送 `SELECT 1` 阻止 MySQL连接判定为闲置[^5]。 3. **防止连接泄漏** `idleTimeout` 清理闲置连接,避免积累导致 `too many connections` 错误[^4]。 > **注意**:需确认 MySQL 的 `wait_timeout`(用 `SHOW VARIABLES LIKE 'wait_timeout';` 查询),确保 `max-lifetime` 比其小至少 1-2 分钟(建议值为 70%-80%)。 --- ### 性能与稳定性建议 [^1][^5] - **避免过度保活**:高频心跳(如每秒)会增加数据库负载,建议 `keepaliveTime ≥ 30秒`。 - **连接泄漏检测**:结合监控工具(如 Prometheus)追踪连接使用情况。 - **云原生优化**:在 Kubernetes 环境中,通过 Sidecar 模式管理连接池,动态调整参数[^5]。
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