Hi Waleed, Are you deleting lots of entities or changing values in some way? Does this only happen when the query uses a cursor passed in from a previous task? When it is happening, if you goto the Datastore Viewer in the dashboard can you run that query?
Robert On Tue, May 17, 2011 at 12:21, Waleed Abdulla <[email protected]> wrote: > I use a chain of tasks to go through a series of entities to process. First > task is inserted by a cron job. It pulls 50 "KnownFeed" entities to process, > and then it inserts the next task passing along a cursor so the next task > continues where the last one finished. Typical pattern, nothing special. And > it's been working for about a year. > In the last few days, I noticed that the first task in a chain tends to fail > too often, and in doing that it doesn't start the chain and the app stops. > It gets retried and it still fails, again and again, for hours. This is > where it breaks: > > query = KnownFeed.all().filter('eta <', end_time).order('eta') > known_feeds = query.fetch(50) > <-- fails with Timeout or DeadlineExceededError > > The query is as simple as it gets, and I haven't changed that code > recently. It's not contention errors or due to too much load because when > the first task in the chain fails, most of the functionality on the app > stops. The interesting thing is that if I kill the task and insert a new > one, the new task runs without problems, even though it runs the same query. > Although I noticed that sometimes the new task fails once then passes on the > retry. > Any thoughts? > Thanks, > Waleed > P.S. Not sure if that's relevant, but when the task does run, it inserts a > series of other tasks and all of them update the "eta" column in the > entities. I thought maybe the index updates take time to update, but that > shouldn't take hours! The table has 300K entities. > > > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/google-appengine?hl=en. > -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
