Very large Markov models often result when modeling realistic computer
systems and networks. We describe an efficient tool for solving gener
al, large Markov models on a typical engineering workstation. It uses
a disk to hold the state-transition-rate matrix (possibly compressed),
a variant of block Gauss-Seidel as the iterative solution method, and
an innovative implementation that involves two parallel processes com
municating by shared memory. We demonstrate its use on two large, real
istic performance models. (C) 1998 Elsevier Science B.V. All rights re
served.