When there is a requirement that a given functionality is only executed by one node at any given time in the cluster, this mechanism can be used as well. If the nodes know of a unique name/id for the functionality (e.g. "check-database-consistency", they can assign that id as the taskId and ask the submit to ignore if the tasks entry already exists in the DB. This way even if multiple nodes ask to submit the same task, only one task will be stored and hence picked up.
Queing serialized execution of tasks is currently not supported, i.e. note that the task is only executed once. Multiple submits are not queued for serialized execution, duplicate submits are discarded/ignored. We could add a submitSerialExecution() capability going forward if required (which would queue the tasks and only serially process each in the cluster).
