General questions about Docker Cloud vs other services

Hi Docker !

I created an account in order to test your services. But first of all, I would like to understand some basics…

We currently use VM to deploy micro services that require arround 512Mo and one VCPU. Today, each time we need to do so (hundreds times per day, each time for a few minutes to few hours), we just deploy a new instance on Digital Ocean. It works great, and costs are limited, according to our pricing policy.

Now, if I try to imagine the same solution on Docker Cloud, I guess that I have to deploy a cluster of nodes. It means that we will pay cluster on Docker Cloud, plus VM’s on cloud provider (AWS, DO, etc…).

Here are my questions :

  • Is cluster resized automatically in order to preserve costs efficiency ?
  • Can we start a container directly from code (like with NodeJS dockerode library), and know in callback that container started ?
  • According to this situation : I have 4 containers to start, and 4 nodes in my cluster : will Docker Cloud instantiate 4 nodes ? Or just start 1 node and run 4 containers on this node (if a node can accept 4 containers, of course) ?
  • What if I start a container, but a node has to be started ? On AWS for example, nodes will take some time to start (not really a problem for us, as far as start callback is called someday) ?

Thanks a lot,