About
A function or an operator has to be:
- and associative
in order to be computed correctly in parallel.
A properly constructed operation is inherently parallelism, so long as the function(s) used to process the elements are:
- and stateless.
Operations upon shared states are critical sections that must be mutually exclusive. Failure to obey this rule opens up the possibility of corrupting the shared state. In other mean, operations have to be free of side effects (no change of any global state)