стратегии задачи обработки HardDeadlineExceededError

У меня есть много задач/сервлетов, которые поражают HardDeadlineExceededError, который оставляет все зависающее в 'все еще выполняющий' состояние.

Сделанная работа может легко превысить 29 вторых порогов.

Я пытаюсь поймать DeadlineExceededException и основывать Исключение для сохранения состояния выхода, но ни один из этих обработчиков исключений не пойман...

Существует ли способ определить, какие задачи находятся в очереди или в настоящее время выполнении?

Есть ли какие-либо другие стратегии того, чтобы справиться с этой ситуацией?

Ситуация, с которой я имею дело, документируется в соответствии с "заголовком" Таймера Запроса.

// task handler for retrieving information from external web services
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {

    String taskRetryCountParam = req.getParameter( "X-AppEngine-TaskRetryCount" );
    int taskRetryCount = (taskRetryCountParam==null) ? 0 : Integer.parseInt(taskRetryCountParam);
            // look up the persistent 'task' and mark it as 'running'

    logger.info( this.getClass().getName() + ".doPost( "+ taskId + " ) retryCount=" + taskRestryCount );


    // Do lots of heavy lifting here 
    // like calling external web services using URL fetch service
            // and saving the contents into our database.

            // look up the persistent 'task' and mark it as 'completed'

    } catch ( DeadlineExceededException deadline ) {
        // got this deadline exception
                    // look up the persistent 'task' and mark it as 'errored - try again'
        logger.warning( "DeadlineExceeded Exception while loading content " + deadline.getMessage() );
        resp.setStatus( HttpServletResponse.SC_REQUEST_TIMEOUT );

        }
    } catch ( Exception unknown ) {
        // got some unknown exception
                    // look up the persistent 'task' and mark it as 'errored - cancelled'
        logger.severe( "General Exception while loading content  exception:" + unknown.getMessage() );
        resp.setStatus( HttpServletResponse.SC_OK );

    }
}

Вот записи файла журнала, когда я вхожу в эту ситуацию... Кажется, что мои транзакции базы данных занимают слишком много времени, когда это прибывает время в.

  W 05-30 12:42PM 09.535
  Error for /loadstatus
  com.google.apphosting.runtime.HardDeadlineExceededError: This request (083793d1091c2ca3) started at 2010/05/30 19:41:39.814 UTC and was still executing at 2010/05/30 19:42:09.529 UTC.
    at java.lang.Object.wait(Native Method)
    at java.lang.Object.wait(Object.java:443)
    at java.util.concurrent.TimeUnit.timedWait(Unknown Source)
    at com.google.apphosting.runtime.AsyncFuture.get(AsyncFuture.java:60)
    at com.google.apphosting.runtime.ApiProxyImpl$AsyncApiFuture.get(ApiProxyImpl.java:326)
    at com.google.apphosting.runtime.ApiProxyImpl$AsyncApiFuture.get(ApiProxyImpl.java:217)
    at com.google.apphosting.runtime.ApiProxyImpl.doSyncCall(ApiProxyImpl.java:131)
    at com.google.apphosting.runtime.ApiProxyImpl.access$000(ApiProxyImpl.java:43)
    at com.google.apphosting.runtime.ApiProxyImpl$1.run(ApiProxyImpl.java:104)
    at com.google.apphosting.runtime.ApiProxyImpl$1.run(ApiProxyImpl.java:102)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.apphosting.runtime.ApiProxyImpl.makeSyncCall(ApiProxyImpl.java:102)
    at com.google.apphosting.runtime.ApiProxyImpl.makeSyncCall(ApiProxyImpl.java:43)
    at com.google.apphosting.api.ApiProxy.makeSyncCall(ApiProxy.java:98)
    at com.google.appengine.api.datastore.DatastoreApiHelper.makeSyncCall(DatastoreApiHelper.java:58)
    at com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(TransactionImpl.java:42)
    at com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(TransactionImpl.java:56)
    at com.google.appengine.api.datastore.TransactionImpl.commit(TransactionImpl.java:66)
    at org.datanucleus.store.appengine.DatastoreTransaction.commit(DatastoreTransaction.java:61)
    at org.datanucleus.store.appengine.DatastoreXAResource.commit(DatastoreXAResource.java:88)
    at org.datanucleus.transaction.Transaction.commit(Transaction.java:149)
    at org.datanucleus.transaction.TransactionManager.commit(TransactionManager.java:95)
    at org.datanucleus.TransactionImpl.internalCommit(TransactionImpl.java:390)
    at org.datanucleus.TransactionImpl.commit(TransactionImpl.java:258)
    at org.datanucleus.jdo.JDOTransaction.commit(JDOTransaction.java:83)
    at org.datanucleus.store.appengine.jdo.DatastoreJDOTransaction.commit(DatastoreJDOTransaction.java:56)
    
  C 05-30 12:42PM 09.629
  Uncaught exception from servlet
  com.google.apphosting.runtime.HardDeadlineExceededError: This request (083793d1091c2ca3) started at 2010/05/30 19:41:39.814 UTC and was still executing at 2010/05/30 19:42:09.529 UTC.
    at java.lang.Object.wait(Native Method)
    at java.lang.Object.wait(Object.java:443)
    at java.util.concurrent.TimeUnit.timedWait(Unknown Source)
    at com.google.apphosting.runtime.AsyncFuture.get(AsyncFuture.java:60)
    at com.google.apphosting.runtime.ApiProxyImpl$AsyncApiFuture.get(ApiProxyImpl.java:326)
    at com.google.apphosting.runtime.ApiProxyImpl$AsyncApiFuture.get(ApiProxyImpl.java:217)
    at com.google.apphosting.runtime.ApiProxyImpl.doSyncCall(ApiProxyImpl.java:131)
    at com.google.apphosting.runtime.ApiProxyImpl.access$000(ApiProxyImpl.java:43)
    at com.google.apphosting.runtime.ApiProxyImpl$1.run(ApiProxyImpl.java:104)
    at com.google.apphosting.runtime.ApiProxyImpl$1.run(ApiProxyImpl.java:102)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.apphosting.runtime.ApiProxyImpl.makeSyncCall(ApiProxyImpl.java:102)
    at com.google.apphosting.runtime.ApiProxyImpl.makeSyncCall(ApiProxyImpl.java:43)
    at com.google.apphosting.api.ApiProxy.makeSyncCall(ApiProxy.java:98)
    at com.google.appengine.api.datastore.DatastoreApiHelper.makeSyncCall(DatastoreApiHelper.java:58)
    at com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(TransactionImpl.java:42)
    at com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(TransactionImpl.java:56)
    at com.google.appengine.api.datastore.TransactionImpl.commit(TransactionImpl.java:66)
    at org.datanucleus.store.appengine.DatastoreTransaction.commit(DatastoreTransaction.java:61)
    at org.datanucleus.store.appengine.DatastoreXAResource.commit(DatastoreXAResource.java:88)
    at org.datanucleus.transaction.Transaction.commit(Transaction.java:149)
    at org.datanucleus.transaction.TransactionManager.commit(TransactionManager.java:95)
    at org.datanucleus.TransactionImpl.internalCommit(TransactionImpl.java:390)
    at org.datanucleus.TransactionImpl.commit(TransactionImpl.java:258)
    at org.datanucleus.jdo.JDOTransaction.commit(JDOTransaction.java:83)
    at org.datanucleus.store.appengine.jdo.DatastoreJDOTransaction.commit(DatastoreJDOTransaction.java:56)
    
  W 05-30 12:42PM 09.644
  A serious problem was encountered with the process that handled this request, causing it to exit. This is likely to cause a new process to be used for the next request to your application. If you see this message frequently, you may be throwing exceptions during the initialization of your application. (Error code 104)