Accession Number : ADA301368

Title :   Communication Overhead on the Intel Paragon, IBM SP2 and Meiko CS-2.

Descriptive Note : Contract rept.,

Corporate Author : INSTITUTE FOR COMPUTER APPLICATIONS IN SCIENCE AND ENGINEERING HAMPTON VA

Personal Author(s) : Bokhari, Shahid H.

PDF Url : ADA301368

Report Date : SEP 1995

Pagination or Media Count : 20

Abstract : Interprocessor communication overhead is a crucial measure of the power of parallel computing systems--its impact can severely limit the performance of parallel programs. This report presents measurements of communication overhead on three contemporary commercial multicomputer systems: the Intel Paragon, the IBM SP2 and the Meiko CS-2. In each case the time to communicate between processors is presented as a function of message length. The time for global synchronization and memory access is discussed. The performance of these machines in emulating hypercubes and executing random pair-wise exchanges is also investigated.It is shown that the interprocessor communication time depends heavily on the specific communication pattern required. These observations contradict the commonly held belief that communication over-head on contemporary machines is independent of the placement of tasks on processors. The information presented in this report permits the evaluation of the efficiency of parallel algorithm implementations against standard baselines.

Descriptors :   *COMPUTATIONS, *COMPUTER COMMUNICATIONS, *INTERFACES, *PARALLEL PROCESSORS, ALGORITHMS, INTEROPERABILITY, EFFICIENCY, PARALLEL PROCESSING, TIME, MEMORY DEVICES, BASE LINES, LENGTH, EMPLACEMENT, PATTERNS, ACCESS, MULTIPROCESSORS, COMMUNICATION AND RADIO SYSTEMS, MESSAGE PROCESSING.

Subject Categories : Computer Hardware

Distribution Statement : APPROVED FOR PUBLIC RELEASE