[petsc-users] CG+GAMG convergence issues in GHEP Krylov-Schur for some MPI runs

[Denis Davydov]

Jose,

Even when I have PETSc --with-debugging=1 and SLEPc picks it up during configure, 
i don’t seem to have debug symbols in resulting SLEPc lib (make stage):

warning: no debug symbols in executable (-arch x86_64)

Same when starting a debugger:
warning: (x86_64) /usr/local/opt/slepc/real/lib/libslepc.3.6.dylib empty dSYM file detected, dSYM was created with an executable with no debug info.

C/Fortran flags seems to have debug flags:

Using C/C++ linker: /usr/local/bin/mpicc
Using C/C++ flags: -Wl,-multiply_defined,suppress -Wl,-multiply_defined -Wl,suppress -Wl,-commons,use_dylibs -Wl,-search_paths_first  -fPIC -Wall -Wwrite-strings -Wno-strict-aliasing -Wno-unknown-pragmas -g3 -O0
Using Fortran linker: /usr/local/bin/mpif90
Using Fortran flags: -Wl,-multiply_defined,suppress -Wl,-multiply_defined -Wl,suppress -Wl,-commons,use_dylibs -Wl,-search_paths_first  -fPIC -Wall -Wno-unused-variable -ffree-line-length-0 -Wno-unused-dummy-argument -g -O0

Any ideas?

Kind regards,
Denis 

> On 3 Nov 2015, at 12:20, Jose E. Roman <jroman at dsic.upv.es> wrote:
> 
> I am answering the SLEPc-related questions:
> - Having different number of iterations when changing the number of processes is normal.
> - Yes, if you do not destroy the EPS solver, then the preconditioner would be reused.
> 
> Regarding the segmentation fault, I have no clue. Not sure if this is related to GAMG or not. Maybe running under valgrind could provide more information.
> 
> Jose

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20151103/6bac7a13/attachment.html>