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我有很多正在触及HardDeadlineExceededError的任务/ servlet，这些任务正在让一切都处于“仍在执行”状态。用于处理的任务策略HardDeadlineExceededError
正在完成的工作可以轻松超过29秒的阈值。
我试图抓住DeadlineExceededException和基础例外，以保存退出 状态，但这些都不例外处理程序被抓的......
有没有一种方法来确定哪些任务是在队列或正在执行？
有没有其他的策略来处理这种情况？
我正在处理的情况记录在"The Request Timer"标题下。
// 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);
}
}
这里是日志文件条目，当我进入这个情况......看来，我的数据库事务正在当谈到时间太长。
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)
您应该可以捕捉到[DeadlineExceededException]（http://code.google.com/appengine/docs/java/runtime.html#The_Request_Timer）。你可以发布你的一些代码吗？ – 2010-05-30 21:24:12
@Matthew：我没有做GAE，但是'HardDeadlineExceededError'听起来不像是一个'Exception'。 – BalusC 2010-05-31 00:16:12
@巴洛斯，我没有说这是。 'DeadlineExceededException'和'HardDeadlineExceededError'是两回事。前者可以被抓到。后者不能，如果你花费大约一秒钟的时间来处理前者，则抛出后者。 – 2010-05-31 00:28:35