Hi Hong and Jed, Many thanks for replying. It would indeed be nice if the error messages from MUMPS were less cryptic!
1) I have tried smaller matrices although given how my problem is set up a jump is difficult to avoid. But a good idea that I will try. 2) I did try various ordering but not the one you suggested. 3) Tracing the error through the MUMPS code suggest a rather abrupt termination of the program (there should be more error messages if, for example, memory was a problem). I therefore thought it might be an interface problem rather than one with mumps and turned to the petsc-users group first. 4) I've tried superlu_dist but it also crashes (also unclear as to why) at which point I decided to try mumps. The fact that both crash would again indicate a common (memory?) problem. I'll try a few more things before asking the MUMPS developers. Thanks again for your help! Samar On Feb 24, 2014, at 11:47 AM, Hong Zhang <[email protected]> wrote: > Samar: > The crash occurs in > ... > [161]PETSC ERROR: Error in external library! > [161]PETSC ERROR: Error reported by MUMPS in numerical factorization phase: > INFO(1)=-1, INFO(2)=48 > > for very large matrix, likely memory problem as you suspected. > I would suggest > 1. run problems with increased sizes (not jump from a small one to a very > large one) and observe memory usage using > '-ksp_view'. > I see you use '-mat_mumps_icntl_14 1000', i.e., percentage of estimated > workspace increase. Is it too large? > Anyway, this input should not cause the crash, I guess. > 2. experimenting with different matrix ordering -mat_mumps_icntl_7 <> (I > usually use sequential ordering 2) > I see you use parallel ordering -mat_mumps_icntl_29 2. > 3. send bug report to mumps developers for their suggestion. > > 4. try other direct solvers, e.g., superlu_dist. > > … > > etc etc. The above error I can tell has something to do with processor 48 > (INFO(2)) and so forth but not the previous one. > > The full output enabled with -mat_mumps_icntl_4 3 looks as in the attached > file. Any hints as to what could be giving this > error would be very much appreciated. > > I do not know how to interpret this output file. mumps developer would give > you better suggestion on it. > I would appreciate to learn as well :-) > > Hong
