This should be a little better now: https://cloudplatform.googleblog.com/2018/05/Increase-performance-while-reducing-costs-with-the-new-App-Engine-scheduler.htm

This should be a little better now: https://cloudplatform.googleblog.com/2018/05/Increase-performance-while-reducing-costs-with-the-new-App-Engine-scheduler.html https://cloudplatform.googleblog.com/2018/05/Increase-perfor... But yeah, you should definitely do your own load testing. GKE or Flex are probably better choices if you need more control. (I work for GCP)