GAE configuration & Billing

[ana...@madebyfire.com]

Google App Engine: Few weeks back I have developed an RoR application in GAE with aditional resources as CloudSQL and Storage Bucket. 

Our application is very simple CMS site. Here the app size details, Application size not more than - 200Mb. Storage - 90MB SQL - 100MB

I have chosen free trail so I got 300$ as Credit limit. Since its a Ruby we can't choose standard env so we used Flex. We have developed this site as UAT environment. So obviously we don't have much traffic appx not more than 50 vists per day. But within 20 days all my Credit gone. 

Also I have used lowest CPU, min max instance count and SQL Storage size.

So why its charging more? Is this normal? Is there a different billing metrics for free and paid?

[Nicholas (Google Cloud Support)]

The usage billed for all the resources you describe depends on many factors.  While the size of an application and the volume content may be small, the usage may be much greater.

App Engine flexible environment bills per instance hour where each instance hour costs a certain amount for vCPU, memory and storage.  Depending on activity and scaling settings, it's possible for an application to scale quickly and consume many instance hours per hour of actual operation.  One can also incur costs for egress traffic.

For Cloud SQL, the cost for instance operation depends on the instance class and its storage, similar in principle to the App Engine flexible environment.  This too can incur network egress costs.

Lastly, Cloud Storage costs are incurred for storage and network traffic.

I would recommend reviewing the linked pricing documentation and checking it against the resources you were billed for displayed in the Billing section of the Cloud Console.  If you find that the usage and costs do not align with what's documented, I would suggest you file a support request for the billing team.