[petsc-users] [beginner question] Different communicators in the two objects: Argument # 1 and 2 flag 3!

[Niklas Fischer]

Am 22.04.2014 14:02, schrieb Jed Brown:
> Niklas Fischer <niklas at niklasfi.de> writes:
>> thank you for your inputs. Unfortunately MPI does not seem to be the
>> issue here. The attachment contains a simple MPI hello world program
>> which runs flawlessly (I will append the output to this mail) and I have
>> not encountered any problems with other MPI programs. My question still
>> stands.
> The output below is amazingly ugly and concerning.  Matt answered your
> question, but in your build system, you should not be adding
> -DPETSC_CLANGUAGE_CXX; that is a configure-time option, not something
> that your code can change arbitrarily.  Your makefile should include
> $PETSC_DIR/conf/variables (and conf/rules if you want, but not if you
> want to write your own rules).
Thank you for your advice. As I stated earlier, this is just a test 
case. I normally use (your) cmake module when using PETSc.
>
>> mpirun -np 2 ./mpitest
>>
>> librdmacm: couldn't read ABI version.
>> librdmacm: assuming: 4
>> CMA: unable to get RDMA device list
>> --------------------------------------------------------------------------
>> [[44086,1],0]: A high-performance Open MPI point-to-point messaging module
>> was unable to find any relevant network interfaces:
>>
>> Module: OpenFabrics (openib)
>>     Host: dornroeschen.igpm.rwth-aachen.de
>>
>> Another transport will be used instead, although this may result in
>> lower performance.
>> --------------------------------------------------------------------------
>> librdmacm: couldn't read ABI version.
>> librdmacm: assuming: 4
>> CMA: unable to get RDMA device list
>> Hello world from processor dornroeschen.igpm.rwth-aachen.de, rank 0 out
>> of 2 processors
>> Hello world from processor dornroeschen.igpm.rwth-aachen.de, rank 1 out
>> of 2 processors
>> [dornroeschen.igpm.rwth-aachen.de:128141] 1 more process has sent help
>> message help-mpi-btl-base.txt / btl:no-nics
>> [dornroeschen.igpm.rwth-aachen.de:128141] Set MCA parameter
>> "orte_base_help_aggregate" to 0 to see all help / error messages
About the MPI output: I have asked the system administrator about this, 
and he is of the oppinion that everything is as it should be. Initially, 
I found the messages concerning as well, but all they are really saying 
is that MPI defaults to using a slower link to exchange messages.

Greetings,
Niklas Fischer