Question

I have a low-load application which experienced latency spikes (requests taking up to 10s to return) due to loading requests, as seen in the logs:

This request caused a new process to be started for your application, and thus caused your application code to be loaded for the first time.

Here I assume that “new process” means “new instance”.

In order to avoid this, I fixed the number of idle instances to exactly one (max=1 and min=1), so there is always one instance running (“resident instance”) and GAE shouldn’t start new ones. Billing is enabled.

However, I still experience loading requests. Why? Can anything be done about this?

Answer 1

Idle instances are “reserve” instances – they are meant to handle spikes when traffic increases, not the “normal” traffic. Idle instances are used only during the spin-up of the dynamic instances.

So, when you have one idle instance and no dynamic instances running and you get a request, than the idle instance should handle the request, but a new dynamic instance will still be spun up.