Transputer System

The star model depicted in Fig.4a and described by equations (6) has been tested in T805 transputer system. We outline here only the results of the experiments, more technical details can be found in [BDM99]. The application tested was a distributed search for a pattern in a text file. The experiments were organized such that computations and communications did not overlap. Processing rates ($A_i$) were measured for each PE as an average rate of 100 experiments in searching a given 300000-byte file. Communication rates and startup-times ($C_i, S_i$) were measured in a set of experiments in which the originator sent to PEs messages of changing size. In all experiments the size of returned data was constant. In Fig. 8 we present the difference between the expected and measured execution time. The difference is in the range $[-1.5\%,1.5\%]$.

Figure 8: Relative difference between the expected and measured execution time for eight transputers vs size $V$ of the searched file.