* vector means that `host0` should compute 1000 flops while `host1` will compute 2000 flops. A matrix of
* communications' sizes of ``[0, 1, 2, 3]`` specifies the following data exchanges:
*
- * +-----------+-------+------+
- * |from \\ to | host0 | host1|
- * +===========+=======+======+
- * |host0 | 0 | 1 |
- * +-----------+-------+------+
- * |host1 | 2 | 3 |
- * +-----------+-------+------+
+ * - from host0: [ to host0: 0 bytes; to host1: 1 byte ]
+ *
+ * - from host1: [ to host0: 2 bytes; to host1: 3 bytes ]
+ *
+ * Or, in other words:
*
* - From host0 to host0: 0 bytes are exchanged
+ *
* - From host0 to host1: 1 byte is exchanged
+ *
* - From host1 to host0: 2 bytes are exchanged
+ *
* - From host1 to host1: 3 bytes are exchanged
*
* In a parallel execution, all parts (all executions on each hosts, all communications) progress exactly at the
