On Tue, Oct 25, 2011 at 12:28 PM, Garth N. Wells <[email protected]> wrote: > On 25 October 2011 11:18, Johannes Ring <[email protected]> wrote: >> On Mon, Oct 24, 2011 at 10:14 PM, Garth N. Wells <[email protected]> wrote: >>> On 24 October 2011 12:57, Johannes Ring <[email protected]> wrote: >>>> This failure was expected and not Martin's fault.The problem is the >>>> stokes-iterative C++ demo, which is problematic when run in parallel >>>> (parallel testing has been turned off on this buildbot slave until >>>> now). >>>> >>>> I have done some manual testing with two and up to five processes and >>>> the demo fails only (but not always) when run with three or five >>>> processes. Sometimes I get a segmentation violation: >>>> >>>> [1]PETSC ERROR: >>>> ------------------------------------------------------------------------ >>>> [1]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation, >>>> probably memory access out of range >>>> [1]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger >>>> [1]PETSC ERROR: or see >>>> http://www.mcs.anl.gov/petsc/petsc-as/documentation/troubleshooting.html#Signal[1]PETSC >>>> ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS X to >>>> find memory corruption errors >>>> [1]PETSC ERROR: configure using --with-debugging=yes, recompile, link, and >>>> run >>>> [1]PETSC ERROR: to get more information on the crash. >>>> [1]PETSC ERROR: --------------------- Error Message >>>> ------------------------------------ >>>> [1]PETSC ERROR: Signal received! >>>> [1]PETSC ERROR: >>>> ------------------------------------------------------------------------ >>>> >>>> Other times I get this error: >>>> >>>> Warning -- row partitioning does not line up! Partitioning incomplete! >>>> [2]PETSC ERROR: MatHYPRE_IJMatrixCreate() line 76 in src/dm/da/utils/mhyp.c >>>> [2]PETSC ERROR: PCSetUp_HYPRE() line 112 in src/ksp/pc/impls/hypre/hypre.c >>>> [2]PETSC ERROR: PCSetUp() line 795 in src/ksp/pc/interface/precon.c >>>> [2]PETSC ERROR: KSPSetUp() line 237 in src/ksp/ksp/interface/itfunc.c >>>> [2]PETSC ERROR: KSPSolve() line 353 in src/ksp/ksp/interface/itfunc.c >>>> Process 2: Soln norm: 0 >>>> >>>> Any ideas? Is it a bug in DOLFIN? The demo works fine in parallel when >>>> using Trilinos instead of PETSc. >>>> >>> >>> There is a very nasty bug in the Oneiric OpenMPI. I had a frustrating >>> week tracking this down. >> >> Is this a bug in OpenMPI 1.4.3 and is it reported somewhere? > > No that I'm aware of. I tracked down an example of the bug in a SCOTCH > call to MPI_Allgather which randomly returned an obviously wrong > result.
Ok. >> It would >> be good to fix this in Ubuntu (see below). >> > > I'm not going to bother tracking it down in Ubuntu because I've > identified an MPI bug in Ubuntu in the past and it was confirmed, but > Ubuntu didn't bother releasing a fix. MPI is too specialised for them > to care. Ok, I see. I will turn off parallel testing on this buildbot then. Johannes _______________________________________________ Mailing list: https://launchpad.net/~dolfin Post to : [email protected] Unsubscribe : https://launchpad.net/~dolfin More help : https://help.launchpad.net/ListHelp
