Marathon vs Kubernetes vs Docker Swarm on DC/OS with Docker containers

I'll try to break down the unique aspects of each container orchestration framework on Mesos.

Use Docker Swarm if:

• You want to use the familiar Docker API to launch Docker containers on Mesos.
• Swarm may eventually provide an API to talk to Kubernetes (even K8s-Mesos) too.
• See: http://www.techrepublic.com/article/docker-and-mesos-like-peanut-butter-and-jelly/

Use Kubernetes-Mesos if:

• You want to launch K8s Pods, which are groups of containers co-scheduled and co-located together, sharing resources.
• You want to launch a service alongside one or more sidekick containers (e.g. log archiver, metrics monitor) that live next to the parent container.
• You want to use the K8s label-based service-discovery, load-balancing, and replication control.
• See http://kubernetesio.blogspot.com/2015/04/kubernetes-and-mesosphere-dcos.html

Use Marathon if:

• You want to launch Docker or non-Docker long-running apps/services.
• You want to use Mesos attributes for constraint-based scheduling.
• You want to use Application Groups and Dependencies to launch, scale, or upgrade related services.
• You want to use health checks to automatically restart unhealthy services or rollback unhealthy deployments/upgrades.
• You want to integrate HAProxy or Consul for service discovery.
• You want to launch and monitor apps through a web UI or REST API.
• You want to use a framework built from the start with Mesos in mind.

Use Chronos if:

• You want to launch Docker or non-Docker tasks that are expected to exit.
• You want to schedule a task to run at a specific time/schedule (a la cron).
• You want to schedule a DAG workflow of dependent tasks.
• You want to launch and monitor jobs through a web UI or REST API.
• You want to use a framework built from the start with Mesos in mind.

Though it's a bit outdated, it may be helpful to read What's the difference between Apache's Mesos and Google's Kubernetes, to get some of the basics right. Also, note that Mesos operates on a different level than Kubernetes/Marathon/Chronos. Last but not least, see Docker Swarm + Mesos by Timothy Chen, keeping in mind that Marathon and Swarm can operate simultaneously on the same Mesos cluster.