Dept. of Computer Science and Engineering
Oregon Graduate Center
A study was made of some of the characteristics, capabilities, and limitations of the iPSC concurrent computer manufactured by the Intel Corporation. Initial experiments with test programs measured the large amount of time required to send and receive messages between nodes and between the cube manager and the nodes. Programs adapted to run concurrently will have the greatest speedup over the same program executed serially if the computational time is large relative to the time spent passing messages. A large-scale computational chemistry program (named ECEPP83) that calculates the global minimum energy of peptide structures (a peptide is a small protein) was ported and adapted to execute on the iPSC computer. The data entry and checking portion of the original code was ported to the 286/310 Intel computer that serves as a manager of the 32 to 128 CPU's (nodes) of the iPSC. The data for each structure is sent by the manager to a separate node which reports its results back to the host or system manager and then is assigned another structure. This adaptation is able to concurrently minimize the energy for 32 chemical structures a maximum of approximately 17 times faster than the same data can be utilized serially on a VAX 11-780 computer. A user manual was written to assist the user in assembling the input data file.
Larrabee, Alan Roger, "Adaptation of a large-scale computational chemistry program to the iPSC concurrent computer" (1986). Scholar Archive. 213.