Parallelization of ITOUGH2 using PVM

ITOUGH2 inversions are computationally intensive because the forward problem must be solved many times to evaluate the objective function for different parameter combinations or to numerically calculate sensitivity coefficients. Most of these forward runs are independent from each other and can therefore be performed in parallel. Message passing based on the Parallel Virtual Machine (PVM) system has been implemented into ROUGH2 to enable parallel processing of ITOUGH2 jobs on a heterogeneous network of Unix workstations. This report describes the PVM system and its implementation into ITOUGH2. Instructions are given for installing PVM, compiling ITOUGH2-PVM for use on a workstation cluster, the preparation of an ITOUGH2 input file under PVM, and the execution of an ITOUGHZPVM application. Examples are discussed, demonstrating the use of ITOUGH2-PVM. ITOUGH2-PVM i ABSTRACT