Spark

• par - a parallelism construct in Haskell program.
• A combinator that (explicitly) initiates or sparks a thunk for (possible) parallel evaluation.
• Sparking a thunk amounts to adding a pointer to the thunk to the PE's spark pool.
• A sparked thunk may be (but need not be) evaluated in parallel; sparks may be discarded if there are too many of them.
• A PE keeps its waiting thunks in its spark pool, which may migrate to an idle PE.