[petsc-users] Error using Metis with PETSc installed with MUMPS

[Pierre Jolivet]

Victoria, please keep the list in copy.

> I am not understanding how can I switch to ParMetis if it does not appear in the options of -mat_mumps_icntl_7.In the options I only have Metis and not ParMetis.


You need to use -mat_mumps_icntl_28 2 -mat_mumps_icntl_29 2

Barry, I don’t think we can programmatically shut off this warning, it’s guarded by a bunch of KEEP() values, see src/dana_driver.F:4707, which are only settable/gettable by people with access to consortium releases.
I’ll ask the MUMPS people for confirmation.
Note that this warning is only printed to screen with the option -mat_mumps_icntl_4 2 (or higher), so this won’t show up for standard runs.

Thanks,
Pierre

> On 1 Nov 2023, at 5:52 PM, Barry Smith <bsmith at petsc.dev> wrote:
> 
> 
>   Pierre,
> 
>    Could the PETSc MUMPS interface "turn-off" ICNTL(6) in this situation so as to not trigger the confusing warning message from MUMPS?
> 
>   Barry
> 
>> On Nov 1, 2023, at 12:17 PM, Pierre Jolivet <pierre at joliv.et> wrote:
>> 
>> 
>> 
>>> On 1 Nov 2023, at 3:33 PM, Zhang, Hong via petsc-users <petsc-users at mcs.anl.gov> wrote:
>>> 
>>> Victoria,
>>> "** Maximum transversal (ICNTL(6)) not allowed because matrix is distributed
>>> Ordering based on METIS"
>> 
>> This warning is benign and appears for every run using a sequential partitioner in MUMPS with a MATMPIAIJ.
>> (I’m not saying switching to ParMETIS will not make the issue go away)
>> 
>> Thanks,
>> Pierre
>> 
>> $ ../../../../arch-darwin-c-debug-real/bin/mpirun -n 2 ./ex2 -pc_type lu -mat_mumps_icntl_4 2
>> Entering DMUMPS 5.6.2 from C interface with JOB, N =   1          56
>>       executing #MPI =      2, without OMP
>> 
>>  =================================================
>>  MUMPS compiled with option -Dmetis
>>  MUMPS compiled with option -Dparmetis
>>  MUMPS compiled with option -Dpord
>>  MUMPS compiled with option -Dptscotch
>>  MUMPS compiled with option -Dscotch
>>  =================================================
>> L U Solver for unsymmetric matrices
>> Type of parallelism: Working host
>> 
>>  ****** ANALYSIS STEP ********
>> 
>>  ** Maximum transversal (ICNTL(6)) not allowed because matrix is distributed
>>  Processing a graph of size:        56 with           194 edges
>>  Ordering based on AMF 
>>  WARNING: Largest root node of size        26 not selected for parallel execution
>> 
>> Leaving analysis phase with  ...
>>  INFOG(1)                                       =               0
>>  INFOG(2)                                       =               0
>> […]
>> 
>>> Try parmetis.
>>> Hong
>>> From: petsc-users <petsc-users-bounces at mcs.anl.gov> on behalf of Victoria Rolandi <victoria.rolandi93 at gmail.com>
>>> Sent: Tuesday, October 31, 2023 10:30 PM
>>> To: petsc-users at mcs.anl.gov <petsc-users at mcs.anl.gov>
>>> Subject: [petsc-users] Error using Metis with PETSc installed with MUMPS
>>>  
>>> Hi, 
>>> 
>>> I'm solving a large sparse linear system in parallel and I am using PETSc with MUMPS. I am trying to test different options, like the ordering of the matrix. Everything works if I use the -mat_mumps_icntl_7 2  or -mat_mumps_icntl_7 0 options (with the first one, AMF, performing better than AMD), however when I test METIS -mat_mumps_icntl_7 5 I get an error (reported at the end of the email).
>>> 
>>> I have configured PETSc with the following options: 
>>> 
>>> --with-cc=mpiicc --with-cxx=mpiicpc --with-fc=mpiifort  --with-scalar-type=complex --with-debugging=0 --with-precision=single --download-mumps --download-scalapack --download-parmetis --download-metis
>>> 
>>> and the installation didn't give any problems.
>>> 
>>> Could you help me understand why metis is not working? 
>>> 
>>> Thank you in advance,
>>> Victoria 
>>> 
>>> Error:
>>> 
>>>  ****** ANALYSIS STEP ********
>>>  ** Maximum transversal (ICNTL(6)) not allowed because matrix is distributed
>>>  Processing a graph of size:    699150 with      69238690 edges
>>>  Ordering based on METIS
>>> 510522 37081376 [100] [10486 699150]
>>> Error! Unknown CType: -1
>> 
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20231101/ea9a6ffb/attachment.html>