The effective bandwidth beff measures the accumulated bandwidth of the communication network of a parallel and/or distributed computing system. Several message sizes, communication patterns and methods are used. The algorithm uses an average to take into account that in real applications short and long messages result in different bandwidth values.
beff = | logavg | ( | logavgcartesian pattern | (sumL (maxmthd (maxrep ( b(cartes.pat.,L,mthd,rep) | )))/21 ), |
logavgrandom pattern | (sumL (maxmthd (maxrep ( b(random pat.,L,mthd,rep) | )))/21 ) | |||
) |
with
First approach from Karl Solchenbach, Hans-Joachim Plum and Gero Ritzenhoefer [1,2] was based on the bi-section bandwidth.
Due to several problems a redesign was done by the b_eff group. This redesign tries not to violate the rules defined by Rolf Hempel in [3] and by William Gropp and Ewing Lusk in [4].
Each run of the benchmark on a paricular system results in an output file. the last line of this output file reports e.g.
b_eff = 9709.549 MB/s = 37.928 * 256 PEs with 128 MB/PE on sn6715 hwwt3e 2.0.4.71 unicosmk CRAY T3E
This line reports
Draft: b_eff.c (version 3.1)
Pallas Effective Bandwidth Benchmark
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