Just a quick update, it seems based on the above-linked repository, that there could be one explanation:
if MessageProcessorServlet <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessageProcessorServlet.java> creates an instance of MessagePurger <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessagePurger.java> (extends Thread) and starts it, this thread will run forever unless interrupted, since it has a "while (true)" loop in its run() method. MessageProcessorServlet <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessageProcessorServlet.java> should call interrupt() on the MessagePurger <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessagePurger.java> during MessageProcessorServlet.destroy() <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessageProcessorServlet.java>. If the servlet isn't destroyed, though, or is destroyed without a call to destroy(), the MessagePurger <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessagePurger.java> thread might run long enough (as here) to be killed by the runtime. Or, given that in this case there doesn't appear to be any error text with the log line, perhaps these are simply long-running MessagePurger <https://github.com/GoogleCloudPlatform/firebase-appengine-backend/blob/master/src/main/java/com/google/cloud/solutions/flexenv/backend/MessagePurger.java> threads which *were *properly destroyed, albeit after a long run. I hope this is helpful, let me know your thoughts and any feedback on whether this is the library you're using. Cheers, Nick Cloud Platform Support On Tuesday, July 5, 2016 at 12:51:54 PM UTC-4, Nick (Cloud Platform Support) wrote: > > Hey Olof, > > Apologies for the slight delay. I'm still looking into any possible cause. > Could you share any of the information mentioned in my last message to help > speed this along? I'm looking at > https://github.com/GoogleCloudPlatform/firebase-appengine-backend right > now. Is this the library you're using? > > Sincerely, > > Nick > Cloud Platform Community Support > > On Friday, July 1, 2016 at 5:00:20 AM UTC-4, Olof Gunnarsson wrote: >> >> I don't fully understand the logs, but it looks like it's older >> background threads. The timestamps in the screenshot are 5 hours apart. >> The log messages "onAuthenticated" and "onDataChange" are Firebase >> callbacks. These log messages are not written after a couple of days, and >> they are also not executed (I delete stuff from Firebase in onDataChange, >> but the deletions stop after a couple of days) >> >> Attached is a better view of the log. >> >> >> >> On Friday, July 1, 2016 at 1:48:10 AM UTC+2, Nick (Cloud Platform >> Support) wrote: >>> >>> Hey Olof, >>> >>> This is interesting. Could you clarify whether the logs are associated >>> with recent calls, or whether they are perhaps older background threads >>> which are closing due to their age? It appears the logs output got a bit >>> mangled as well during copy-paste, is there any chance a more faithful >>> reproduction of the complete logs info, or a screenshot with all fields >>> expanded, could be provided? >>> >>> Cheers, >>> >>> Nick >>> Cloud Platform Community Support >>> >>> On Tuesday, June 28, 2016 at 5:24:02 AM UTC-4, Olof Gunnarsson wrote: >>>> >>>> >>>> I'm using Google Cloud Endpoints and Google App Engine with Firebase >>>> (java). Firebase calls are done in a background thread "/_ah/background", >>>> which works fine. However, after a couple of days the background thread >>>> stops executing. Calls to GAE still work but calls to Firebase are not >>>> executed. A restart of the instance makes everything work again. >>>> >>>> I get these in the log which contains log messages from my calls to >>>> Firebase, and then suddenly I don't get anymore of these logs and the >>>> calls >>>> to Firebase stops executing. >>>> >>>> Any ideas? >>>> >>>> 17:02:46.795GET0 B56,999.2 sUnknown/_ah/background >>>> 17:02:46.795GET0 B34,555.2 sUnknown/_ah/background >>>> 17:02:46.795GET0 B17,351 sUnknown/_ah/background >>>> 17:02:46.795GET0 B17,350.9 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,925.6 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,923.4 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,866 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,131.1 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,103.3 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,101.8 sUnknown/_ah/background >>>> 17:02:46.795GET0 B8,079.2 sUnknown/_ah/background >>>> >>> -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. 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