Why charging more then My usages?

[Love Sharma]

Hi,

I have been observing my instance creation stuff closely. And it seems, lots of time I am getting charge more than I use. (Please check screenshot)

- Instance created: 2 (Out of 2, it seems only 1 instance is active)

- Billed instances: 3 (Why?, I am not benefitted by the 3rd instance, then why charging more?)

Above issue is very common (the ratio is 2:5 sometime), lots of time I am being charged more without using it.

Please look into it, 

Thanks,

Love Sharma

[Adam (Cloud Platform Support)]

As I have your app id from another thread I'll reply here about this question. App Engine by default keeps a number of instances idle, and is controllable using the 'max_idle_instances' parameter in app.yaml. The value is 'auto' if you don't specify anything, and you can see the current value in the Cloud Console under 'App Engine' -> 'Versions' (you may need to click 'More Columns').

These absolutely do benefit you as those instances will already be available to serve requests in the event of a traffic spike. You can reduce the max idle instances but this can adversely affect latency. As mentioned in the documentation:

• Max Idle Instances - Setting Max Idle Instances allows App Engine to shut down idle instances above the specified limit so they won't consume additional quota or create charges. However, fewer idle instances also means that the App Engine Scheduler may have to spin up new instances if you experience a spike in traffic -- potentially increasing user-visible latency for your app.