I am not saving any entities but I am putting more than one task in queue. It depends of the data that current task is processing. Let's say two tasks (always less then five).
At the end of 'transaction' I will have two tasks in queue or none. This usually works, but sometimes I get this ConcurrentModificationException exception. Complete application chunk works eventually because task with execute again and will finish correctly, but it would be nice to understand this exception so that I can avoid it. On Oct 28, 1:58 am, Tim Hoffman <zutes...@gmail.com> wrote: > If you are not saving any entities why are you using a transaction to > put the task into the queue. > > The idea of a queuing a task transactionally is that the task doesn't > get fired if the transaction fails (ie you save of entities fails). > > Seems completely redundant > > Rgds > > T > > On Oct 21, 11:18 pm, Matija <matija.jerko...@gmail.com> wrote: > > > > > Hi, > > I am > > usinghttp://code.google.com/appengine/docs/java/taskqueue/overview.html#Ta... > > way to enqueue two tasks in transaction. But I am not saving any > > datastore entities. I am using objectify. > > > I got this message: > > > java.util.ConcurrentModificationException: too much contention on > > these datastore entities. please try again. > > at > > com.google.appengine.api.datastore.DatastoreApiHelper.translateError(Datast > > oreApiHelper.java: > > 39) > > at > > com.google.appengine.api.datastore.DatastoreApiHelper.makeSyncCall(Datastor > > eApiHelper.java: > > 75) > > at > > com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(Transaction > > Impl.java: > > 44) > > at > > com.google.appengine.api.datastore.TransactionImpl.makeSyncCall(Transaction > > Impl.java: > > 52) > > at > > com.google.appengine.api.datastore.TransactionImpl.commit(TransactionImpl.j > > ava: > > 64) > > > When this happened only one task needed to be added to queue, so why > > this error ? -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
