[petsc-users] Irritating behavior of MUMPS with PETSc

[Gunnar Jansen]

You are right about the queuing system. The job is submitted with a PBS
script specifying the number of nodes/processors. On the cluster petsc is
configured in a module environment which sets the appropriate flags for
compilers/rules etc.

The same exact job script on the same exact nodes with a standard krylov
method does not give any trouble but executes nicely on all processors (and
also give the correct result).

Therefore my suspicion is a missing flag in the mumps interface. Is this
maybe rather a topic for the mumps-dev team?

Best, Gunnar



2014-06-25 15:52 GMT+02:00 Dave May <dave.mayhem23 at gmail.com>:

> This sounds weird.
>
> The launch line you provided doesn't include any information regarding how
> many processors (nodes/nodes per core to use). I presume you are using a
> queuing system. My guess is that there could be an issue with either (i)
> your job script, (ii) the configuration of the job scheduler on the
> machine, or (iii) the mpi installation on the machine.
>
> Have you been able to successfully run other petsc (or any mpi) codes with
> the same launch options (2 nodes, 3 procs per node)?
>
> Cheers.
>   Dave
>
>
>
>
> On 25 June 2014 15:44, Gunnar Jansen <jansen.gunnar at gmail.com> wrote:
>
>> Hi,
>>
>> i try to solve a problem in parallel with MUMPS as the direct solver. As
>> long as I run the program on only 1 node with 6 processors everything works
>> fine! But using 2 nodes with 3 processors each gets mumps stuck in the
>> factorization.
>>
>> For the purpose of testing I run the ex2.c on a resolution of 100x100
>> (which is of course way to small for a direct solver in parallel).
>>
>> The code is run with :
>> mpirun ./ex2 -on_error_abort -pc_type lu -pc_factor_mat_solver_package
>> mumps -ksp_type preonly -log_summary -options_left -m 100 -n 100
>> -mat_mumps_icntl_4 3
>>
>> The petsc-configuration I used is:
>> --prefix=/opt/Petsc/3.4.4.extended --with-mpi=yes
>> --with-mpi-dir=/opt/Openmpi/1.9a/ --with-debugging=no --download-mumps
>>  --download-scalapack --download-parmetis --download-metis
>>
>> Is this common behavior? Or is there an error in the petsc configuration
>> I am using here?
>>
>> Best,
>> Gunnar
>>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20140625/d0df613b/attachment.html>