ABSTRACT |
The NWT computer system available at the NAL since February 1993 comprises two system administrators,n processing elements (where n was 140 at the beginning, and is 166 at present) and a crossbar network, and operates as a distributed-memory message-passing MIMD computer. Each processing element itself is a vector computer. This paper reports measurements of two pairs of the characteristic parameters, (t-infinity,n1/2) and (t-infinity,s1/2), of the NWT with SIMD computing on a single processing element and with MIMD computing in the local memory access, respectively. Furthermore the significance of the obtained results is interpreted, and several hardware parameters are estimated. The obtained results in this paper apply only to the NWT system software during the period April to June 1993 after which substantial improvements have been achieved with the NWT performance. |