US Patent 7103626 Partitioning in distributed computer system

A distributed computer system includes a first subnet including a first group of endnodes, each endnode in the first group of endnodes having a unique destination location identification (DLID) within the first subnet. A second subnet in the distributed computer system includes a second group of endnodes, each endnode in the second group of endnodes having a unique DLID within the second subnet. A communication fabric is physically coupled to the first group of endnodes and the second group of endnodes. A partitioning mechanism associates a first partition key to every DLID in the first subnet for enabling communication between the first group of endnodes over the communication fabric. The partitioning mechanism associates a second partition key to every DLID in the second subnet for enabling communication between the second group of endnodes over the communication fabric.