The `nano-quickstart` is an even smaller configuration, targeting a machine with 1 CPU and 4GB memory. It is meant for limited evaluations in resource constrained environments, such as small Docker containers.
The other configurations are intended for general use single-machine deployments. They are sized for hardware roughly based on Amazon's i3 series of EC2 instances.
The startup scripts for these example configurations run a single ZK instance along with the Druid services. You can choose to deploy ZK separately as well.
The example configurations run the Druid Coordinator and Overlord together in a single process using the optional configuration `druid.coordinator.asOverlord.enabled=true`, described in the [Coordinator configuration documentation](../configuration/index.html#coordinator-operation).
While example configurations are provided for very large single machines, at higher scales we recommend running Druid in a [clustered deployment](../tutorials/cluster.md), for fault-tolerance and reduced resource contention.