Terrible cpu-time and ApiProxy$CancelledException - google-app-engine

Question

What I have done is a movie website. It will show the latest movie info and showtimes.
I have a cron job to update all the playing movies. However, whenever it runs, it throws a ApiProxy$CancelledException and have a terrible cpu-time about 4706364 cpu_ms 4644739 api_cpu_ms that make my APP exceeds quota very soon. Could someone help me. Thanks!!
The number of the playing movies is around 25, and the number of the showtimes is around 650.
My code
// Get all the playing movies from the datasotre
Query query = pm.newQuery(Movie.class);
query.setFilter("playing == true");
List<Movie> playingMovies = (List<Movie>) query.execute();
// Update every playing movie
for (Movie m : playingMovies) {
// getMovie() will return a movie with latest movie info and showtimes
Movie leMovie = getMovie(m.getId());
leMovie.setKey(m.getKey());
leMovie.setFans(m.getFans());
// because leMovie has the latest showtimes so I need to delete the older showtimes
m.getShowtimeList().clear();
pm.makePersistent(leMovie);
}
My Movie Class
#PersistenceCapable(identityType = IdentityType.APPLICATION)
public class Movie {
#Persistent
private Set<Key> fans;
#PrimaryKey
#Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
#Persistent
private String id;
#Persistent
private boolean playing;
#Persistent
private int gate;
#Persistent
private String picUrl;
#Persistent
private String mainName;
#Persistent(mappedBy = "movie")
#Element(dependent = "true")
private List<Showtime> showtimeList;
//......
The Exception
2011-08-22 10:30:00.138
/cron/update-movie
com.google.apphosting.api.ApiProxy$CancelledException: The API call datastore_v3.Put() was explicitly cancelled.
at com.google.apphosting.runtime.ApiProxyImpl$5.get(ApiProxyImpl.java:298)
at com.google.apphosting.runtime.ApiProxyImpl$5.get(ApiProxyImpl.java:296)
at com.google.appengine.api.utils.FutureWrapper.get(FutureWrapper.java:67)
at com.google.appengine.api.datastore.FutureHelper$CumulativeAggregateFuture.get(FutureHelper.java:144)
at com.google.appengine.api.datastore.FutureHelper.getInternal(FutureHelper.java:72)
at com.google.appengine.api.datastore.FutureHelper.quietGet(FutureHelper.java:33)
at com.google.appengine.api.datastore.DatastoreServiceImpl$2.runInternal(DatastoreServiceImpl.java:113)
at com.google.appengine.api.datastore.DatastoreServiceImpl$2.runInternal(DatastoreServiceImpl.java:110)
at com.google.appengine.api.datastore.TransactionRunner.runInTransaction(TransactionRunner.java:31)
at com.google.appengine.api.datastore.DatastoreServiceImpl.put(DatastoreServiceImpl.java:110)
at com.google.appengine.api.datastore.DatastoreServiceImpl.put(DatastoreServiceImpl.java:94)
at org.datanucleus.store.appengine.RuntimeExceptionWrappingDatastoreService.put(RuntimeExceptionWrappingDatastoreService.java:94)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.put(DatastorePersistenceHandler.java:180)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.put(DatastorePersistenceHandler.java:139)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.put(DatastorePersistenceHandler.java:134)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.updateObject(DatastorePersistenceHandler.java:536)
at org.datanucleus.state.JDOStateManagerImpl.flush(JDOStateManagerImpl.java:4576)
at org.datanucleus.ObjectManagerImpl.flushInternal(ObjectManagerImpl.java:2814)
at org.datanucleus.ObjectManagerImpl.flush(ObjectManagerImpl.java:2754)
at org.datanucleus.ObjectManagerImpl.preCommit(ObjectManagerImpl.java:2893)
at org.datanucleus.TransactionImpl.internalPreCommit(TransactionImpl.java:369)
at org.datanucleus.TransactionImpl.commit(TransactionImpl.java:256)
at org.datanucleus.ObjectManagerImpl.close(ObjectManagerImpl.java:801)
at org.datanucleus.jdo.JDOPersistenceManager.close(JDOPersistenceManager.java:271)
at com.mm.servlet.UpdateMovieServlet.doGet(UpdateMovieServlet.java:100)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.apphosting.utils.servlet.ParseBlobUploadFilter.doFilter(ParseBlobUploadFilter.java:97)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.runtime.jetty.SaveSessionFilter.doFilter(SaveSessionFilter.java:35)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at com.google.apphosting.runtime.jetty.AppVersionHandlerMap.handle(AppVersionHandlerMap.java:249)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)
at com.google.apphosting.runtime.jetty.RpcRequestParser.parseAvailable(RpcRequestParser.java:76)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at com.google.apphosting.runtime.jetty.JettyServletEngineAdapter.serviceRequest(JettyServletEngineAdapter.java:135)
at com.google.apphosting.runtime.JavaRuntime.handleRequest(JavaRuntime.java:262)
at com.google.apphosting.base.RuntimePb$EvaluationRuntime$2.handleRequest(RuntimePb.java:9819)
at com.google.net.rpc.impl.RpcUtil.handleRequest(RpcUtil.java:445)
at com.google.net.rpc.impl.RpcUtil.runRpcInApplication(RpcUtil.java:414)
at com.google.net.rpc.impl.Server$RpcTask.runInContext(Server.java:579)
at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:454)
at com.google.tracing.TraceContext.runInContext(TraceContext.java:694)
at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:332)
at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:324)
at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:452)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:636)
C 2011-08-22 10:30:00.144
Uncaught exception from servlet
com.google.apphosting.api.ApiProxy$CancelledException: The API call datastore_v3.Put() was explicitly cancelled.
at com.google.apphosting.runtime.ApiProxyImpl$5.get(ApiProxyImpl.java:298)
at com.google.apphosting.runtime.ApiProxyImpl$5.get(ApiProxyImpl.java:296)
at com.google.appengine.api.utils.FutureWrapper.get(FutureWrapper.java:67)
at com.google.appengine.api.datastore.FutureHelper$CumulativeAggregateFuture.get(FutureHelper.java:144)
at com.google.appengine.api.datastore.FutureHelper.getInternal(FutureHelper.java:72)
at com.google.appengine.api.datastore.FutureHelper.quietGet(FutureHelper.java:33)
at com.google.appengine.api.datastore.DatastoreServiceImpl$2.runInternal(DatastoreServiceImpl.java:113)
at com.google.appengine.api.datastore.DatastoreServiceImpl$2.runInternal(DatastoreServiceImpl.java:110)
at com.google.appengine.api.datastore.TransactionRunner.runInTransaction(TransactionRunner.java:31)
at com.google.appengine.api.datastore.DatastoreServiceImpl.put(DatastoreServiceImpl.java:110)
at com.google.appengine.api.datastore.DatastoreServiceImpl.put(DatastoreServiceImpl.java:94)
at org.datanucleus.store.appengine.RuntimeExceptionWrappingDatastoreService.put(RuntimeExceptionWrappingDatastoreService.java:94)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.put(DatastorePersistenceHandler.java:180)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.put(DatastorePersistenceHandler.java:139)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.put(DatastorePersistenceHandler.java:134)
at org.datanucleus.store.appengine.DatastorePersistenceHandler.updateObject(DatastorePersistenceHandler.java:536)
at org.datanucleus.state.JDOStateManagerImpl.flush(JDOStateManagerImpl.java:4576)
at org.datanucleus.ObjectManagerImpl.flushInternal(ObjectManagerImpl.java:2814)
at org.datanucleus.ObjectManagerImpl.flush(ObjectManagerImpl.java:2754)
at org.datanucleus.ObjectManagerImpl.preCommit(ObjectManagerImpl.java:2893)
at org.datanucleus.TransactionImpl.internalPreCommit(TransactionImpl.java:369)
at org.datanucleus.TransactionImpl.commit(TransactionImpl.java:256)
at org.datanucleus.ObjectManagerImpl.close(ObjectManagerImpl.java:801)
at org.datanucleus.jdo.JDOPersistenceManager.close(JDOPersistenceManager.java:271)
at com.mm.servlet.UpdateMovieServlet.doGet(UpdateMovieServlet.java:100)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.apphosting.utils.servlet.ParseBlobUploadFilter.doFilter(ParseBlobUploadFilter.java:97)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.runtime.jetty.SaveSessionFilter.doFilter(SaveSessionFilter.java:35)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at com.google.apphosting.runtime.jetty.AppVersionHandlerMap.handle(AppVersionHandlerMap.java:249)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)
at com.google.apphosting.runtime.jetty.RpcRequestParser.parseAvailable(RpcRequestParser.java:76)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at com.google.apphosting.runtime.jetty.JettyServletEngineAdapter.serviceRequest(JettyServletEngineAdapter.java:135)
at com.google.apphosting.runtime.JavaRuntime.handleRequest(JavaRuntime.java:262)
at com.google.apphosting.base.RuntimePb$EvaluationRuntime$2.handleRequest(RuntimePb.java:9819)
at com.google.net.rpc.impl.RpcUtil.handleRequest(RpcUtil.java:445)
at com.google.net.rpc.impl.RpcUtil.runRpcInApplication(RpcUtil.java:414)
at com.google.net.rpc.impl.Server$RpcTask.runInContext(Server.java:579)
at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:454)
at com.google.tracing.TraceContext.runInContext(TraceContext.java:694)
at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:332)
at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:324)
at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:452)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:636)
W 2011-08-22 10:30:00.451
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)

Answer 1

Maybe it is too late to reply...
Usual request time is about one minute, if "getMovie(m.getId());" request info from some other server it may take long and go through your minute.
GAE task has more time to run jobs so better you use your cron to enqueue a new task and let appengine do your work in the background.
Task t = new Task();
t.setUrl(URL_SERVLET_TO_UPDATE_MOVIES);
//submit task
TaskReference tr = queue.add(t);
This servlet runs the job of updating movies.
Even needing more time (lets assume you got plenty of movies there) you can get only a few number of movies per query, actualize them, get a Cursor (works as range) and enqueue a new task with that cursor as parameter to the servlet.
This new task will start from the next movie you have to actualize (thanks to the Cursor) and you will have full time to do your job. You can chain task until your job is done.
At your servlet look for a cursor as param:
String encodedCursor = req.getParameter(CURSOR_PARAM);
if ( encodedCursor != null){
oldCursor = Cursor.fromWebSafeString(encodedCursor);
}
You can use this Cursor to query from the last movie you queried.
Get a new cursor from the new query and add it as parameter to the new task.
Task t = new Task();
t.setUrl(PROCESSOR_SERVLET);
//add cursor as parameter
t.addParameter(CURSOR_PARAM, cursor.toWebSafeString());
//submit task
TaskReference tr = queue.add(t);
Using Task and cursors you will get your job done in the background avoiding time limits.
Of course, there are quotas over there...
Doc about cursors:
https://developers.google.com/appengine/docs/java/datastore/queries#Query_Cursors