Wildfly 8.0.0.Final + EntityManager + PostgreSQL-事務中空閑

Question

我在Wildfly 8.0.0.Final上運行以下代碼：

@Stateful
public class MyJPABean<T> {

    @PersistenceContext(unitName = "myUnitName")
    private EntityManager em;

    @TransactionAttribute(TransactionAttributeType.REQUIRED)
    public void write(T entity) {
        em.persist(entity);
        em.flush();
    }

    @TransactionAttribute(TransactionAttributeType.REQUIRED)
    public void update(T entity) {
        em.merge(entity);
    }
}

寫入和更新方法都稱為並行方法，因為它們是直接從另一個處理HTTP請求的類中調用的：

@Path("api")
public class MyApiController {

    private MyJPABean<MyJpaModel> jpaBean;

    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public void handlePost(MyJpaModel myJpaModel) {
       jpaBean.write(myJpaModel);
    }
}

一些“寫入”方法調用是成功的，但有時，當“寫入”方法被多個線程並行調用時，它開始掛在em.persist（entity）上。

在PostgreSQL服務器端，我可以看到查詢狀態為“ idle in transaction”的事務：“ select nextval（'hibernate_sequence'）”或插入從我剛剛嘗試保留的實體創建的查詢。

發生此問題時，我將無法再保留實體。 一切都掛在em.persist（entity）上。 我要么無法殺死Wildfly進程，要么必須用-9信號殺死它。

我做錯了什么嗎？

一段時間后（發生超時），我可以在應用程序日志中看到以下警告：

16:44:30,590 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff7f000101:-231d9b5d:55030494:2d in state  RUN
16:44:30,591 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper Worker 0) ARJUNA012095: Abort of action id 0:ffff7f000101:-231d9b5d:55030494:2d invoked while multiple threads active within it.
16:44:30,591 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper Worker 0) ARJUNA012108: CheckedAction::check - atomic action 0:ffff7f000101:-231d9b5d:55030494:2d aborting with 1 threads active!
16:44:30,598 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff7f000101:-231d9b5d:55030494:35 in state  RUN
16:44:31,090 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff7f000101:-231d9b5d:55030494:2d in state  CANCEL
16:44:31,092 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012378: ReaperElement appears to be wedged: com.arjuna.ats.arjuna.coordinator.TwoPhaseCoordinator.afterCompletion(TwoPhaseCoordinator.java:487)
com.arjuna.ats.arjuna.coordinator.TwoPhaseCoordinator.afterCompletion(TwoPhaseCoordinator.java:463)
com.arjuna.ats.arjuna.coordinator.TwoPhaseCoordinator.cancel(TwoPhaseCoordinator.java:118)
com.arjuna.ats.arjuna.AtomicAction.cancel(AtomicAction.java:215)
com.arjuna.ats.arjuna.coordinator.TransactionReaper.doCancellations(TransactionReaper.java:377)
com.arjuna.ats.internal.arjuna.coordinator.ReaperWorkerThread.run(ReaperWorkerThread.java:78)

16:44:31,100 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff7f000101:-231d9b5d:55030494:35 in state  SCHEDULE_CANCEL
16:44:31,594 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff7f000101:-231d9b5d:55030494:2d in state  CANCEL_INTERRUPTED
16:44:31,595 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:ffff7f000101:-231d9b5d:55030494:2d -- worker marked as zombie and TX scheduled for mark-as-rollback
16:44:31,596 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper Worker 1) ARJUNA012095: Abort of action id 0:ffff7f000101:-231d9b5d:55030494:35 invoked while multiple threads active within it.
16:44:31,597 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012110: TransactionReaper::check successfuly marked TX 0:ffff7f000101:-231d9b5d:55030494:2d as rollback only
16:44:31,597 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper Worker 1) ARJUNA012108: CheckedAction::check - atomic action 0:ffff7f000101:-231d9b5d:55030494:35 aborting with 1 threads active!
16:44:31,600 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012117: TransactionReaper::check timeout for TX 0:ffff7f000101:-231d9b5d:55030494:35 in state  CANCEL
16:44:31,602 WARN  [com.arjuna.ats.arjuna] (Transaction Reaper) ARJUNA012378: ReaperElement appears to be wedged: org.apache.log4j.AppenderSkeleton.doAppend(AppenderSkeleton.java:231)

作為jdbc驅動程序，使用“ postgresql-9.2-1004.jdbc41”。 PostgreSQL服務器版本為“ 9.3”。 我在類路徑上也有c3p0，但是即使刪除此依賴項，問題仍然存在。

Answer 1

我已經使用JAX-RS，EJB和JPA准備了一個示例應用程序-https: //github.com/aparnachaudhary/prototypes/tree/master/jaxrs-db-access 。 我使用JMeter腳本通過多個線程訪問REST端點。 但是我無法重現PostgreSQL 9.3，postgresql-9.3-1103.jdbc41.jar和WildFly 8.1.0.Final的問題。