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Container creation happens at a component called ContainerManager (which can reuse a lot of today's invoker's code, like the container factories). The ContainerManager is a cluster-singleton (see Clustered Singleton Invoker for HA on Mesos). It talks to the API of the underlying container orchestrator to create new containers. If the Controller has no more capacity for a certain action, that is, it exhausted its containers known for that action, it requests more containers from the ContainerManager.
The **ContainerManagerAgent** is an extension to the ContainerManager. It is placed on each node in the system to either orchestrate the full container lifecycle (no orchestrator case) or provide the means necessary to fulfill some bits of the container lifecycle (like pause/unpause in the Kubernetes case).
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