> You are better off communicating what to do with the data, rather than sharing the data. Not if you actually want to distribute the work over several cores.

> You are better off communicating what to do with the data, rather than sharing the data. Not if you actually want to distribute the work over several cores. Example: Your data is partitioned into 4 segments A, B, C, and D. In step 1, node X processes A&B and node Y processes C&D; in step 2, node X processes A&D and node Y processes C&B. If A, B, C, and D are large, this is a prime example where shared memory trumps message passing in terms of performance. If you think that's a contrived case: dense matrix multiplication behaves like this.