A model for performance evaluation of message passing architectures in spatial data processing

We give a first formulation of a model for evaluating performances of a message passing architecture parallel machine in the context of spatial data processing. We consider 2-dimensional data of the type `region´ and analyze operations of union and intersection between them. On the basis of the characteristics of manipulation algorithms and of the architecture we individuate as the best way of implementing them, we propose and validate through experiments a model able to estimate time required to execute union or intersection operations between two regions of arbitrary shape as a function of a small number of parameters describing input data. Though derived on a specific machine, the model obtained is of general validity, since only the values of numerical constants are dependant by the machine used. Such a model is the first necessary step in tackling the issue of query optimization for spatial data in a parallel environment. The work is a part of a more general research programme aiming at studying the best approach to take advantage from parallel architectures for spatial data processing