Theoretical maximum value of <max-concurrent requests> for Google AppEngine Backend

Question

Does anyone know if there is a maximum value for <max-concurrent-request> -setting for Back-Up instances for AppEngine? Ie, the backend will be able to accept and serve requests until it completely runs out of memory or processor, if I set <max-concurrent-requests> to gig-billion? Or are there other quotas or external restrictions? (I think TCP port numbers, thread handles, ...?)

Answer 1

From https://cloud.google.com/appengine/docs/python/config/appconfig :

max_concurrent_requests:

Additionally. An instance can accept the number of simultaneous requests for automatic scaling before the scheduler creates a new instance (Default: 8, Maximum: 80 ). You may experience increased API latency if this setting is too large. Note that the scheduler can create a new instance up to the actual maximum number of requests.

Answer 2

Quote from GAE documentation

"Specifies the maximum number of requests that each instance can process at the same time. If unset, App Engine determines the concurrent request limit dynamically."

Thus, they did not specify a limit, but also indicated that GAE would determine the limit dynamically, which could be based on the number of instances that you have and which instances you configured. The ability of these instances to process your requests is likely to determine the maximum size.