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我有很多正在觸及HardDeadlineExceededError的任務/ servlet，這些任務正在讓一切都處於「仍在執行」狀態。用於處理的任務策略HardDeadlineExceededError
正在完成的工作可以輕鬆超過29秒的閾值。
我試圖抓住DeadlineExceededException和基礎例外，以保存退出 狀態，但這些都不例外處理程序被抓的......
有沒有一種方法來確定哪些任務是在隊列或正在執行？
有沒有其他的策略來處理這種情況？
我正在處理的情況記錄在"The Request Timer"標題下。
// 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);
}
}
這裏是日誌文件條目，當我進入這個情況......看來，我的數據庫事務正在當談到時間太長。
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$1.run(ApiProxyImpl.java:102)
at java.security.AccessController.doPrivileged(Native Method)
at com.google.apphosting.runtime.ApiProxyImpl.makeSyncCall(ApiProxyImpl.java:102)
at com.google.apphosting.runtime.ApiProxyImpl.makeSyncCall(ApiProxyImpl.java:43)
at com.google.apphosting.api.ApiProxy.makeSyncCall(ApiProxy.java:98)
at com.google.appengine.api.datastore.DatastoreApiHelper.makeSyncCall(DatastoreApiHelper.java:58)
at com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(TransactionImpl.java:42)
at com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(TransactionImpl.java:56)
at com.google.appengine.api.datastore.TransactionImpl.commit(TransactionImpl.java:66)
at org.datanucleus.store.appengine.DatastoreTransaction.commit(DatastoreTransaction.java:61)
at org.datanucleus.store.appengine.DatastoreXAResource.commit(DatastoreXAResource.java:88)
at org.datanucleus.transaction.Transaction.commit(Transaction.java:149)
at org.datanucleus.transaction.TransactionManager.commit(TransactionManager.java:95)
at org.datanucleus.TransactionImpl.internalCommit(TransactionImpl.java:390)
at org.datanucleus.TransactionImpl.commit(TransactionImpl.java:258)
at org.datanucleus.jdo.JDOTransaction.commit(JDOTransaction.java:83)
at org.datanucleus.store.appengine.jdo.DatastoreJDOTransaction.commit(DatastoreJDOTransaction.java:56)
<snip>
C 05-30 12:42PM 09.629
Uncaught exception from servlet
com.google.apphosting.runtime.HardDeadlineExceededError: This request (083793d1091c2ca3) started at 2010/05/30 19:41:39.814 UTC and was still executing at 2010/05/30 19:42:09.529 UTC.
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:443)
at java.util.concurrent.TimeUnit.timedWait(Unknown Source)
at com.google.apphosting.runtime.AsyncFuture.get(AsyncFuture.java:60)
at com.google.apphosting.runtime.ApiProxyImpl$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)
<snip>
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)
您應該可以捕捉到[DeadlineExceededException]（http://code.google.com/appengine/docs/java/runtime.html#The_Request_Timer）。你可以發佈你的一些代碼嗎？ – 2010-05-30 21:24:12
@Matthew：我沒有做GAE，但是'HardDeadlineExceededError'聽起來不像是一個'Exception'。 – BalusC 2010-05-31 00:16:12
@巴洛斯，我沒有說這是。 'DeadlineExceededException'和'HardDeadlineExceededError'是兩回事。前者可以被抓到。後者不能，如果你花費大約一秒鐘的時間來處理前者，則拋出後者。 – 2010-05-31 00:28:35