Hi Kaan, you're not alone. We noticed the same issue, too. We have server processes making like 20request/second all the time to appengine, and all of the sudden we were experiencing these lingering requests. It all began earlier this year and still continues. Those request don't leave any traces in the logs and keep the TCP connection open very long (like at least 20 minutes). They never give any reponse at all.
The funny thing is, we first encountered these request while connecting from a GCE instance. This was over .appspot.com. The error was gone when we switched the connection to a custom domain. But that didn't last. We then saw this errors on other machines, too - not only from GCE. And they also appeared on the custom domain (SNI SSL) and also over VIP SSL. So I would think it's neither 1) or 2). Instead I would think it is a problem with the Google frontend server instances that get somehow stuck when dispatching the requests. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/b91f237e-33f6-4f6d-88a7-5ec679bb59a1%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
