mesos is private cloud for your data center.
Use available resources in existing cluster.
mesos is less like an cluster management but more like a kernel.
mesos is a distributed system kernel.
so this containers will scale up and down as required.
zookeeper elects new master/scheduler
timeout is also used to kill the master/scheduler.
so if the master/scheduler that failed does not reconnect in the threshold period you will just kill all of the tasks pending there