The answer is different depending on the App Engine environment. GAE Standard for example, supports gradual traffic migration wherein you can enable 'warmup request' to prepare the new instances before those instances serve any traffic.
In contrast, GAE Flex does not support gradual traffic migration which means user requests are sent to those instances before the instances get created. This results to delay/latency (not an outright fail) since the request has to wait until the instance gets up and running. It is possible that request may fail if the request timeouts before the instance is ready. See full article here <https://cloud.google.com/appengine/docs/standard/nodejs/migrating-traffic>. -- 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 google-appengine+unsubscr...@googlegroups.com. To post to this group, send email to google-appengine@googlegroups.com. 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/0cdab1f5-54da-46ed-b21b-8aba5edd5867%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
