Are GAE instances limited to 10 concurrent request?

Question

I\'ve heard from several sources that Google App Engine Instances have a hard limit of 10 concurrent request. I was wondering if someone could clarify what exactly this mean

Answer 1

As of July 12, 2012, it's the latter. The 10 concurrent limit is enforced through a limit on concurrent threads on every runtime. Most of such cases, our scheduler will try to spin up a new instance.

Please also see the e-mail from jonmac on this thread: https://groups.google.com/d/msg/google-appengine/y-LnZ2WYJ5Q/j_w13F4oSSkJ

Answer 2

This has been fixed as of Nov 18th 2013.

The maximum number of requests any GAE instance can process is now configured via the max_concurrent_requests setting eg:

runtime: go
api_version: go1
automatic_scaling:
  max_concurrent_requests: 80

handlers:
  - url: /.*
    script: _go_app

The default is 8 and the maximum is 80.

See https://cloud.google.com/appengine/docs/python/config/appref#automatic_scaling for more info.