Question

我有一个JBoss 6.3 EAP，JPA 2.0，EJB 3.1，CMT JTA网络应用程序。 DB是MSSQL2008R2，使用MS JDBC驱动程序，hibernate 4.2.14。

我有一个看起来像这样的方法，复制一百万个价格实体：

public void doStuff(Date newDate)
{
    List<Prices> prices = dao.getPrices(); //<< 1000000+ prices
    for (Prices price : prices)
    {
        Prices copy = price.clone();
        copy.setDate(newDate);
        entityManager.persist(copy);
        if (newDate.before(someDate))
        {
            price.setDate(someDate);
            entityManager.merge(price);
        }
    }
}

我将JBoss EJB协调器超时设置为一小时，让它运行。第一次内存耗尽后，我将堆大小增加到-Xmx 3G。

代码从凌晨1点24分开始，它在凌晨1点36分结束，然后在凌晨2点24分结束，它因交易错误而失败，并回滚。堆栈跟踪在刷新期间表示它。

 at org.hibernate.ejb.AbstractEntityManagerImpl$CallbackExceptionMapperImpl.mapManagedFlushFailure(AbstractEntityManagerImpl.java:1510) [hibernate-e
ntitymanager-4.2.14.SP1-redhat-1.jar:4.2.14.SP1-redhat-1]

我可以看到，如果我把百万分成10000块并且在每个块之后冲洗，那么它在一小时内甚至不会接近一百万。因此，冲洗显然是一项昂贵的任务。但我认为它在JTA的拦截后提交过程中会隐含地开始冲洗。

我应该只是增加超时并再试一次吗？这是一个由其他几个人使用的DEV数据库，我的代码似乎锁定了价格表，使得MSSQL SMSS无法查询，所以我不想让它无限期地运行。但这只是需要更多时间的问题吗？

开始堆栈跟踪：

02:24:45,157 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff0a14021f:3d218bb8:56009132:22 in state  RUN
02:24:45,169 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper Worker 0) ARJUNA012095: Abort of action id 0:ffff0a14021f:3d218bb8:56009132:22 invoked while multiple threads active within it.
02:24:45,169 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper Worker 0) ARJUNA012108: CheckedAction::check - atomic action 0:ffff0a14021f:3d218bb8:56009132:22 aborting with 1 threads active!
02:24:45,667 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff0a14021f:3d218bb8:56009132:22 in state  CANCEL
02:24:46,209 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff0a14021f:3d218bb8:56009132:22 in state  CANCEL_INTERRUPTED
02:24:46,210 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012120: TransactionReaper::check worker Thread[Transaction Reaper Worker 0,5,main] not responding to interrupt when cancelling TX 0:ffff0a14021f:3d218bb8:56009132:22 -- worker marked as zombie and TX scheduled for mark-as-rollback
02:24:46,210 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012110: TransactionReaper::check successfuly marked TX 0:ffff0a14021f:3d218bb8:56009132:22 as rollback only
02:25:07,968 WARN  [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-/0.0.0.0:8080-1) SQL Error: 0, SQLState: null
02:25:07,968 ERROR [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-/0.0.0.0:8080-1) Transaction cannot proceed STATUS_ROLLEDBACK
02:25:08,085 WARN  [com.arjuna.ats.arjuna] (http-/0.0.0.0:8080-1) ARJUNA012125: TwoPhaseCoordinator.beforeCompletion - failed for SynchronizationImple< 0:ffff0a14021f:3d218bb8:56009132:24, org.hibernate.engine.transaction.synchronization.internal.RegisteredSynchronization@2d633a18 >: javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: could not prepare statement

Answer 1

我把它重写为SQL，并使用了2个entityManager.createNativeQuery调用，而不是程序化的JPA，它在30秒左右完成。

因此，经验教训是，不要为大型数据集担心JPA。在SQL中找出解决方案，然后直接获取JDBC连接。

EJB JPA CMT - 大型数据集上的刷新失败

1 个答案: