Allow me take the opportunity and ask if anybody here is running Elasticsearch with Mesos (and Marathon) using Docker container?

I'm running Elasticsearch nodes on a dedicated Mesos slaves and I’m still not sure how much memory should I allocate to Elasticsearch task e.g. all available memory as reported by Mesos or some smaller amount to leave something for the system? Please note that I'm asking about memory allocated to the Marathon task not about JVM heap size.