Organisational aspects of using parallel computers

Abstract

The ‘cost’ of most computations of a multiple processor system includes components due to the need to communicate data amongst the processors. These costs for a set of global algorithms are examined and a figure of merit is defined—the balance factor is defined for mesh connected processors. In particular the costs of the SUMMATION operator are considered in a wide range of contexts and it is shown that simple extrapolations from few processor/single problem environments have very little relevance to environments with many processors.