Hi, Matt, Thanks a lot for your suggestions. In the following two subroutines,
(1) int mat_vec_product_interface_problem(Mat A, Vec X, Vec Y) for matrix-free GMRES solver (2) int preconditioner_mat_vec(PC pc,Vec X,Vec Y) for shell preconditioner I use the VecScatter() and VecGetArray() to successfully call the parallel GMRES solver to solve my problem. Thanks a lot as usual. Zhengyong On Sat, Jun 30, 2012 at 1:30 PM, Matthew Knepley <knepley at gmail.com> wrote: > On Fri, Jun 29, 2012 at 7:25 PM, RenZhengYong <renzhengyong at > gmail.com>wrote: > >> Dear Petscs, >> >> Use the uniprocessor complex-value based version petsc, I recently >> successfully make a FETI_DP domain >> decomposition approach working for 3D electromagnetic induction (earth) >> problem. The number of iteration of >> the interface problem seems to be scalable with regard to the number of >> sub-domains. >> >> To do this, I had two subroutines for petsc >> >> (1) int mat_vec_product_interface_problem(Mat A, Vec X, Vec Y) for >> matrix-free GMRES solver >> (2) int preconditioner_mat_vec(PC pc,Vec X,Vec Y) for shell >> preconditioner. >> >> Now, I want to solve the interface problem by paralleled GMRES solver so >> that I can solve real large-scale problems. Could you please tell me the >> easiest way to accomplish it. Which specific data structures of petsc >> should be used. I have been using Petsc for 3.5 years, I really want to >> have a try the real MPI-based Petsc. >> > > 1) The solver logic should be parallel already since it only uses calls to > Vec or Mat functions. The problems will be > in building data structures. > > 2) It looks like your two items above are the things to be parallelized > > 3) Decide how to partition the problem > > 4) Use VecScatter() to communicate data along the interface of your > partitions > > I don't think we can give better advice than that without more specific > questions. Note that there is > a current effort to put BDDCinto PETSc. You can see it in petsc-dev, as > PCBDDC. > > Thanks, > > Matt > > >> Thanks in advance. >> Have a nice weekeed >> Zhengyong >> >> >> -- >> Zhengyong Ren >> AUG Group, Institute of Geophysics >> Department of Geosciences, ETH Zurich >> NO H 47 Sonneggstrasse 5 >> CH-8092, Z?rich, Switzerland >> Tel: +41 44 633 37561 >> e-mail: zhengyong.ren at aug.ig.erdw.ethz.ch >> Gmail: renzhengyong at gmail.com >> > > > > -- > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which their > experiments lead. > -- Norbert Wiener > -- Zhengyong Ren AUG Group, Institute of Geophysics Department of Geosciences, ETH Zurich NO H 47 Sonneggstrasse 5 CH-8092, Z?rich, Switzerland Tel: +41 44 633 37561 e-mail: zhengyong.ren at aug.ig.erdw.ethz.ch Gmail: renzhengyong at gmail.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120704/c0cd1981/attachment.html>
