我在使用 JPA-1.0、Hibernate 和 MySQL 5.0.84(innoDB 表)以及 Postgres 8.1.11(不同客户端的不同数据库)的并发事务时遇到问题。我不知道我是否遗漏了一些关于配置的东西,因为我已经阅读了关于 JPA 事务的规范,并且根据我遇到的问题, 我需要为事务注释指定特定的隔离级别。我这样做了,但它只是一起关闭了事务,所以没有任何内容被保留/更新。
我正在做的是,向 Web 服务器(在我的例子中是 tomcat)启动 http posts,然后当 http 请求进入时,它会尝试生成多个数据库事务。 每个事务包含 1 次插入和 2 次更新。但是,问题似乎总是出现在最终更新中,这是基于先前的插入。 所以,我插入记录 A,然后更新记录 B,它是记录 A 的外键。
以下是我在执行单个 http 请求时获得的日志记录:
org.springframework.orm.jpa.JpaTransactionManager:365 - Creating new transaction with name [biz.cytrus.overlord.v2.core.ExecutionLogAPI.create]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT; ''
org.springframework.orm.jpa.JpaTransactionManager:323 - Opened new EntityManager [org.hibernate.ejb.EntityManagerImpl@221f81] for JPA transaction
org.springframework.orm.jpa.JpaTransactionManager:355 - Exposing JPA transaction as JDBC transaction [org.springframework.orm.jpa.vendor.HibernateJpaDialect$HibernateConnectionHandle@9f5742]
org.springframework.orm.jpa.JpaTransactionManager:752 - Initiating transaction commit
org.springframework.orm.jpa.JpaTransactionManager:462 - Committing JPA transaction on EntityManager [org.hibernate.ejb.EntityManagerImpl@221f81]
org.springframework.orm.jpa.JpaTransactionManager:548 - Closing JPA EntityManager [org.hibernate.ejb.EntityManagerImpl@221f81] after transaction
org.springframework.orm.jpa.EntityManagerFactoryUtils:329 - Closing JPA EntityManager
以下是我同时执行多个http请求得到的日志:
org.hibernate.util.JDBCExceptionReporter:357 - SQL Error: 1213, SQLState: 40001
org.hibernate.util.JDBCExceptionReporter:454 - Deadlock found when trying to get lock; try restarting transaction
org.hibernate.event.def.AbstractFlushingEventListener:532 - Could not synchronize database state with session
org.hibernate.exception.LockAcquisitionException: Could not execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:105)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:275)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:168)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:365)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:137)
at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:54)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:467)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:375)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
at $Proxy66.create(Unknown Source)
at biz.cytrus.overlord.v2.web.action.task.LogAction.createLogEntry(LogAction.java:84)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:592)
at net.sourceforge.stripes.controller.DispatcherHelper$6.intercept(DispatcherHelper.java:442)
at net.sourceforge.stripes.controller.ExecutionContext.proceed(ExecutionContext.java:158)
at net.sourceforge.stripes.controller.BeforeAfterMethodInterceptor.intercept(BeforeAfterMethodInterceptor.java:113)
at net.sourceforge.stripes.controller.ExecutionContext.proceed(ExecutionContext.java:155)
at net.sourceforge.stripes.controller.ExecutionContext.wrap(ExecutionContext.java:74)
at net.sourceforge.stripes.controller.DispatcherHelper.invokeEventHandler(DispatcherHelper.java:440)
at net.sourceforge.stripes.controller.DispatcherServlet.invokeEventHandler(DispatcherServlet.java:278)
at net.sourceforge.stripes.controller.DispatcherServlet.service(DispatcherServlet.java:160)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at net.sourceforge.stripes.controller.StripesFilter.doFilter(StripesFilter.java:247)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
at java.lang.Thread.run(Thread.java:595)
Caused by: java.sql.BatchUpdateException: Deadlock found when trying to get lock; try restarting transaction
at com.mysql.jdbc.ServerPreparedStatement.executeBatch(ServerPreparedStatement.java:657)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeBatch(NewProxyPreparedStatement.java:1723)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)
... 48 more
org.springframework.orm.jpa.JpaTransactionManager:893 - Initiating transaction rollback after commit exception
org.springframework.dao.CannotAcquireLockException: Could not execute JDBC batch update; SQL [update application_instances set application_id=?, create_date=?, for_ongoing_task=?, last_log_id=?, last_notified_date=?, name=?, param_string=?, application_status_id=?, status_date=? where id=?]; nested exception is org.hibernate.exception.LockAcquisitionException: Could not execute JDBC batch update
at org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException(SessionFactoryUtils.java:633)
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:97)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:471)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:375)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
at $Proxy66.create(Unknown Source)
at biz.cytrus.overlord.v2.web.action.task.LogAction.createLogEntry(LogAction.java:84)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:592)
at net.sourceforge.stripes.controller.DispatcherHelper$6.intercept(DispatcherHelper.java:442)
at net.sourceforge.stripes.controller.ExecutionContext.proceed(ExecutionContext.java:158)
at net.sourceforge.stripes.controller.BeforeAfterMethodInterceptor.intercept(BeforeAfterMethodInterceptor.java:113)
at net.sourceforge.stripes.controller.ExecutionContext.proceed(ExecutionContext.java:155)
at net.sourceforge.stripes.controller.ExecutionContext.wrap(ExecutionContext.java:74)
at net.sourceforge.stripes.controller.DispatcherHelper.invokeEventHandler(DispatcherHelper.java:440)
at net.sourceforge.stripes.controller.DispatcherServlet.invokeEventHandler(DispatcherServlet.java:278)
at net.sourceforge.stripes.controller.DispatcherServlet.service(DispatcherServlet.java:160)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at net.sourceforge.stripes.controller.StripesFilter.doFilter(StripesFilter.java:247)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
at java.lang.Thread.run(Thread.java:595)
Caused by: org.hibernate.exception.LockAcquisitionException: Could not execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:105)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:275)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:168)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:365)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:137)
at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:54)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:467)
... 39 more
Caused by: java.sql.BatchUpdateException: Deadlock found when trying to get lock; try restarting transaction
at com.mysql.jdbc.ServerPreparedStatement.executeBatch(ServerPreparedStatement.java:657)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeBatch(NewProxyPreparedStatement.java:1723)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)
... 48 more
org.springframework.orm.jpa.JpaTransactionManager:488 - Rolling back JPA transaction on EntityManager [org.hibernate.ejb.EntityManagerImpl@7ca9bd]
org.springframework.orm.jpa.JpaTransactionManager:548 - Closing JPA EntityManager [org.hibernate.ejb.EntityManagerImpl@7ca9bd] after transaction
org.springframework.orm.jpa.EntityManagerFactoryUtils:329 - Closing JPA EntityManager
在尝试解决这个问题时,我尝试在事务注释上设置隔离级别,但这导致数据库没有任何 Activity :
org.springframework.orm.jpa.JpaTransactionManager:365 - Creating new transaction with name [biz.cytrus.overlord.v2.core.ExecutionLogAPI.create]: PROPAGATION_REQUIRED,ISOLATION_REPEATABLE_READ; ''
org.springframework.orm.jpa.JpaTransactionManager:323 - Opened new EntityManager [org.hibernate.ejb.EntityManagerImpl@adddd6] for JPA transaction
org.springframework.orm.jpa.EntityManagerFactoryUtils:329 - Closing JPA EntityManager
如果能帮助我解决这个问题,我将不胜感激。
这是方法中标有注解@Transactional 的代码片段:
Task task = ongoingTaskAPI.findById(taskId);
ExecutionLog executionLog = new ExecutionLog();
executionLog.setStatusDate(new Date());
executionLog.setStatus(status);
executionLog.setApplicationInstance(task.getApplicationInstance());
executionLog.getApplicationInstance().setLastLog(executionLog);
em.persist(executionLog);
实体bean的相关部分如下:
public class ExecutionLog implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer id;
@ManyToOne
@JoinColumn(name="application_instance_id")
private ApplicationInstance applicationInstance;
public class ApplicationInstance implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer id;
@OneToOne
@JoinColumn(name="last_log_id", nullable = true)
private ExecutionLog lastLog;
在任何时候都存在一对一的关系,特定的日志记录只能链接到特定的应用程序实例记录。
所以本质上,我正在做的是创建日志记录,然后更新应用程序实例,以便它链接到与其相关的最新日志记录。这是在单个事务方法中完成的,但在更新应用程序实例记录时似乎会发生故障。但是,这在单个调用上工作正常,但在并发调用上效果不佳。
希望这能让我的问题更加清晰。
最佳答案
您指向最新日志条目的共享“应用程序实例”行正在请求锁定问题。在我看来,顺序将是:
所以两个线程都可以拥有 application_instance 上的共享锁;然后线程 A 阻塞在线程 B 上尝试进行更新,然后线程 B 阻塞在线程 A 上...
我会通过立即获取具有独占锁的应用程序实例来解决这个问题。在直接的 Hibernate 术语中,在加载实体时(session.get 或查询)。
(我还会重新检查您是否真的需要更新 application_instance 以每次都指向最新的日志条目 - 这是一个瓶颈,因为所有事务都需要对其进行同步/序列化。)
关于java - JPA 并发事务,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/5139556/
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