You must be seting KSPSetInitialGuessNonzero() in your code. So either remove that line or use -ksp_type richardson instead of -ksp_type preonly.
Barry > On Jul 22, 2015, at 1:49 PM, Jin, Shuangshuang <[email protected]> > wrote: > > Hi, I’m trying to use PETSc ksp to solve a linear equation with the following > option: “-ksp_type preonly -pc_type lu -pc_factor_mat_ordering_type amd” > > I got an error message below. Does anyone have an idea how it comes from? > > [0]PETSC ERROR: --------------------- Error Message > -------------------------------------------------------------- > [0]PETSC ERROR: > [0]PETSC ERROR: Running KSP of preonly doesn't make sense with nonzero > initial guess > you probably want a KSP type of Richardson > [0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html for > trouble shooting. > [0]PETSC ERROR: Petsc Release Version 3.6.0, Jun, 09, 2015 > [0]PETSC ERROR: Unknown Name on a olympus-openmpi_f-gnu-cxx-complex-opt named > olympus.local by d3m956 Wed Jul 22 11:37:26 2015 > [0]PETSC ERROR: Configure options > PETSC_ARCH=olympus-openmpi_f-gnu-cxx-complex-opt --with-prefix=./ > --with-mpi=1 --with-cc=mpicc --with-fc=mpif90 --with-cxx=mpicxx > --with-c++-support=1 --with-c-support=0 --with-c-language=C++ > --with-fortran=0 --with-scalar-type=complex --with-fortran-kernels=generic > --download-superlu_dist --download-superlu --download-parmetis > --download-metis --download-f2cblaslapack=1 --download-suitesparse > --with-clanguage=c++ --with-shared-libraries=0 --with-x=0 > --with-mpirun=mpirun --with-mpiexec=mpiexec --with-debugging=0 > [0]PETSC ERROR: #1 KSPSolve_PREONLY() line 23 in > /pic/projects/gridpack/software_f/petsc-3.6.0/src/ksp/ksp/impls/preonly/preonly.c > [0]PETSC ERROR: #2 KSPSolve() line 604 in > /pic/projects/gridpack/software_f/petsc-3.6.0/src/ksp/ksp/interface/itfunc.c > [0]PETSC ERROR: #3 p_solve() line 120 in > /pic/projects/gridpack/gridpack-Github/src/math/petsc/petsc_linear_solver_implementation.hpp > terminate called after throwing an instance of > 'gridpack::math::PETScException' > what(): PETSc error (0): Error detected in C PETSc > [olympus:27408] *** Process received signal *** > [olympus:27408] Signal: Aborted (6) > [olympus:27408] Signal code: (-6) > [olympus:27408] [ 0] /lib64/libpthread.so.0 [0x3d2920eca0] > [olympus:27408] [ 1] /lib64/libc.so.6(gsignal+0x35) [0x3d2862ffc5] > [olympus:27408] [ 2] /lib64/libc.so.6(abort+0x110) [0x3d28631a70] > [olympus:27408] [ 3] > /share/apps/gcc/4.6.2/lib64/libstdc++.so.6(_ZN9__gnu_cxx27__verbose_terminate_handlerEv+0x11d) > [0x7f4aa53705bd] > [olympus:27408] [ 4] /share/apps/gcc/4.6.2/lib64/libstdc++.so.6 > [0x7f4aa536e766] > [olympus:27408] [ 5] /share/apps/gcc/4.6.2/lib64/libstdc++.so.6 > [0x7f4aa536e793] > [olympus:27408] [ 6] /share/apps/gcc/4.6.2/lib64/libstdc++.so.6 > [0x7f4aa536e88e] > [olympus:27408] [ 7] > ./ds2.x(_ZNK8gridpack4math31PETScLinearSolverImplementationISt7complexIdEiE7p_solveERKNS0_7VectorTIS3_iEERS6_+0x4cf) > [0x74634f] > [olympus:27408] [ 8] > ./ds2.x(_ZNK8gridpack4math25BaseLinearSolverInterfaceISt7complexIdEiE5solveERKNS0_7VectorTIS3_iEERS6_+0x37) > [0x65e84f] > [olympus:27408] [ 9] > ./ds2.x(_ZNK8gridpack4math13LinearSolverTISt7complexIdEiE7p_solveERKNS0_7VectorTIS3_iEERS6_+0x3b) > [0x68fb89] > [olympus:27408] [10] > ./ds2.x(_ZNK8gridpack4math25BaseLinearSolverInterfaceISt7complexIdEiE5solveERKNS0_7VectorTIS3_iEERS6_+0x37) > [0x65e84f] > [olympus:27408] [11] > ./ds2.x(_ZN8gridpack18dynamic_simulation6DS2App5solveENS0_9DS2Branch5EventE+0x8f0) > [0x656386] > [olympus:27408] [12] ./ds2.x(main+0x41d) [0x64d9b1] > [olympus:27408] [13] /lib64/libc.so.6(__libc_start_main+0xf4) [0x3d2861d9f4] > [olympus:27408] [14] ./ds2.x [0x64d4dd] > [olympus:27408] *** End of error message *** > Abort > > Thanks, > Shuangshuang
