Version 1.3.1

All seems fine to me. Agreed on not needing mlockall - vm.swappiness=1 is the best solution of the 3 options.

Re ES_HEAP_SIZE, Java will tend to its max heap setting anyway - it does not release unused (but claimed) heap memory back to the OS. Yey Java. So ES_HEAP_SIZE=1g is a low risk change.