title: How does Google App Engine Autoscaling work?
body: <p>This question is about Google App Engine quotas and instances.</p>
  
  <p>I deployed a GAE app without specifying any specific scaling algo. From their docs, it seems like the default is auto-scaling. </p>
  
  <p>So when do they scale the app to another instance, i.e. when exactly does a new instance spawn? What request/s causes the second instance to get started and traffic to be split?</p>