superlu_dist options

Fredrik Bengzon fredrik.bengzon at math.umu.se
Fri May 8 17:26:28 CDT 2009


Hi again,
I resorted to using Mumps, which seems to scale very well, in Slepc. 
However I have another question: how do you sort an MPI vector in Petsc, 
and can you get the permutation also?
/Fredrik
 


Barry Smith wrote:
>
> On May 8, 2009, at 11:03 AM, Matthew Knepley wrote:
>
>> Look at the timing. The symbolic factorization takes 1e-4 seconds and 
>> the numeric takes
>> only 10s, out of 542s. MatSolve is taking 517s. If you have a 
>> problem, it is likely there.
>> However, the MatSolve looks balanced.
>
>    Something is funky with this. The 28 solves should not be so much 
> more than the numeric factorization.
> Perhaps it is worth saving the matrix and reporting this as a 
> performance bug to Sherrie.
>
>    Barry
>
>>
>>
>>   Matt
>>
>> On Fri, May 8, 2009 at 10:59 AM, Fredrik Bengzon 
>> <fredrik.bengzon at math.umu.se> wrote:
>> Hi,
>> Here is the output from the KSP and EPS objects, and the log summary.
>> / Fredrik
>>
>>
>> Reading Triangle/Tetgen mesh
>> #nodes=19345
>> #elements=81895
>> #nodes per element=4
>> Partitioning mesh with METIS 4.0
>> Element distribution (rank | #elements)
>> 0 | 19771
>> 1 | 20954
>> 2 | 20611
>> 3 | 20559
>> rank 1 has 257 ghost nodes
>> rank 0 has 127 ghost nodes
>> rank 2 has 143 ghost nodes
>> rank 3 has 270 ghost nodes
>> Calling 3D Navier-Lame Eigenvalue Solver
>> Assembling stiffness and mass matrix
>> Solving eigensystem with SLEPc
>> KSP Object:(st_)
>>  type: preonly
>>  maximum iterations=100000, initial guess is zero
>>  tolerances:  relative=1e-08, absolute=1e-50, divergence=10000
>>  left preconditioning
>> PC Object:(st_)
>>  type: lu
>>   LU: out-of-place factorization
>>     matrix ordering: natural
>>   LU: tolerance for zero pivot 1e-12
>> EPS Object:
>>  problem type: generalized symmetric eigenvalue problem
>>  method: krylovschur
>>  extraction type: Rayleigh-Ritz
>>  selected portion of the spectrum: largest eigenvalues in magnitude
>>  number of eigenvalues (nev): 4
>>  number of column vectors (ncv): 19
>>  maximum dimension of projected problem (mpd): 19
>>  maximum number of iterations: 6108
>>  tolerance: 1e-05
>>  dimension of user-provided deflation space: 0
>>  IP Object:
>>   orthogonalization method:   classical Gram-Schmidt
>>   orthogonalization refinement:   if needed (eta: 0.707100)
>>  ST Object:
>>   type: sinvert
>>   shift: 0
>>  Matrices A and B have same nonzero pattern
>>     Associated KSP object
>>     ------------------------------
>>     KSP Object:(st_)
>>       type: preonly
>>       maximum iterations=100000, initial guess is zero
>>       tolerances:  relative=1e-08, absolute=1e-50, divergence=10000
>>       left preconditioning
>>     PC Object:(st_)
>>       type: lu
>>         LU: out-of-place factorization
>>           matrix ordering: natural
>>         LU: tolerance for zero pivot 1e-12
>>         LU: factor fill ratio needed 0
>>              Factored matrix follows
>>             Matrix Object:
>>               type=mpiaij, rows=58035, cols=58035
>>               package used to perform factorization: superlu_dist
>>               total: nonzeros=0, allocated nonzeros=116070
>>                 SuperLU_DIST run parameters:
>>                   Process grid nprow 2 x npcol 2
>>                   Equilibrate matrix TRUE
>>                   Matrix input mode 1
>>                   Replace tiny pivots TRUE
>>                   Use iterative refinement FALSE
>>                   Processors in row 2 col partition 2
>>                   Row permutation LargeDiag
>>                   Column permutation PARMETIS
>>                   Parallel symbolic factorization TRUE
>>                   Repeated factorization SamePattern
>>       linear system matrix = precond matrix:
>>       Matrix Object:
>>         type=mpiaij, rows=58035, cols=58035
>>         total: nonzeros=2223621, allocated nonzeros=2233584
>>           using I-node (on process 0) routines: found 4695 nodes, 
>> limit used is 5
>>     ------------------------------
>> Number of iterations in the eigensolver: 1
>> Number of requested eigenvalues: 4
>> Stopping condition: tol=1e-05, maxit=6108
>> Number of converged eigenpairs: 8
>>
>> Writing binary .vtu file /scratch/fredrik/output/mode-0.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-1.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-2.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-3.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-4.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-5.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-6.vtu
>> Writing binary .vtu file /scratch/fredrik/output/mode-7.vtu
>> ************************************************************************************************************************ 
>>
>> ***             WIDEN YOUR WINDOW TO 120 CHARACTERS.  Use 'enscript 
>> -r -fCourier9' to print this document            ***
>> ************************************************************************************************************************ 
>>
>>
>> ---------------------------------------------- PETSc Performance 
>> Summary: ----------------------------------------------
>>
>> /home/fredrik/Hakan/cmlfet/a.out on a linux-gnu named medusa1 with 4 
>> processors, by fredrik Fri May  8 17:57:28 2009
>> Using Petsc Release Version 3.0.0, Patch 5, Mon Apr 13 09:15:37 CDT 2009
>>
>>                        Max       Max/Min        Avg      Total
>> Time (sec):           5.429e+02      1.00001   5.429e+02
>> Objects:              1.380e+02      1.00000   1.380e+02
>> Flops:                1.053e+08      1.05695   1.028e+08  4.114e+08
>> Flops/sec:            1.939e+05      1.05696   1.894e+05  7.577e+05
>> Memory:               5.927e+07      1.03224              2.339e+08
>> MPI Messages:         2.880e+02      1.51579   2.535e+02  1.014e+03
>> MPI Message Lengths:  4.868e+07      1.08170   1.827e+05  1.853e+08
>> MPI Reductions:       1.122e+02      1.00000
>>
>> Flop counting convention: 1 flop = 1 real number operation of type 
>> (multiply/divide/add/subtract)
>>                           e.g., VecAXPY() for real vectors of length 
>> N --> 2N flops
>>                           and VecAXPY() for complex vectors of length 
>> N --> 8N flops
>>
>> Summary of Stages:   ----- Time ------  ----- Flops -----  --- 
>> Messages ---  -- Message Lengths --  -- Reductions --
>>                       Avg     %Total     Avg     %Total   counts   
>> %Total     Avg         %Total   counts   %Total
>> 0:      Main Stage: 5.4292e+02 100.0%  4.1136e+08 100.0%  1.014e+03 
>> 100.0%  1.827e+05      100.0%  3.600e+02  80.2%
>>
>> ------------------------------------------------------------------------------------------------------------------------ 
>>
>> See the 'Profiling' chapter of the users' manual for details on 
>> interpreting output.
>> Phase summary info:
>>  Count: number of times phase was executed
>>  Time and Flops: Max - maximum over all processors
>>                  Ratio - ratio of maximum to minimum over all processors
>>  Mess: number of messages sent
>>  Avg. len: average message length
>>  Reduct: number of global reductions
>>  Global: entire computation
>>  Stage: stages of a computation. Set stages with PetscLogStagePush() 
>> and PetscLogStagePop().
>>     %T - percent time in this phase         %F - percent flops in 
>> this phase
>>     %M - percent messages in this phase     %L - percent message 
>> lengths in this phase
>>     %R - percent reductions in this phase
>>  Total Mflop/s: 10e-6 * (sum of flops over all processors)/(max time 
>> over all processors)
>> ------------------------------------------------------------------------------------------------------------------------ 
>>
>>
>>
>>     ##########################################################
>>     #                                                        #
>>     #                          WARNING!!!                    #
>>     #                                                        #
>>     #   This code was compiled with a debugging option,      #
>>     #   To get timing results run config/configure.py        #
>>     #   using --with-debugging=no, the performance will      #
>>     #   be generally two or three times faster.              #
>>     #                                                        #
>>     ##########################################################
>>
>>
>> Event                Count      Time (sec)     
>> Flops                             --- Global ---  --- Stage ---   Total
>>                  Max Ratio  Max     Ratio   Max  Ratio  Mess   Avg 
>> len Reduct  %T %F %M %L %R  %T %F %M %L %R Mflop/s
>> ------------------------------------------------------------------------------------------------------------------------ 
>>
>>
>> --- Event Stage 0: Main Stage
>>
>> STSetUp                1 1.0 1.0467e+01 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 8.0e+00  2  0  0  0  2   2  0  0  0  2     0
>> STApply               28 1.0 5.1775e+02 1.0 3.15e+07 1.1 1.7e+02 
>> 4.2e+03 2.8e+01 95 30 17  0  6  95 30 17  0  8     0
>> EPSSetUp               1 1.0 1.0482e+01 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 4.6e+01  2  0  0  0 10   2  0  0  0 13     0
>> EPSSolve               1 1.0 3.7193e+02 1.0 9.59e+07 1.1 3.5e+02 
>> 4.2e+03 9.7e+01 69 91 35  1 22  69 91 35  1 27     1
>> IPOrthogonalize       19 1.0 3.4406e-01 1.1 6.75e+07 1.1 2.3e+02 
>> 4.2e+03 7.6e+01  0 64 22  1 17   0 64 22  1 21   767
>> IPInnerProduct       153 1.0 3.1410e-01 1.0 5.63e+07 1.1 2.3e+02 
>> 4.2e+03 3.9e+01  0 53 23  1  9   0 53 23  1 11   700
>> IPApplyMatrix         39 1.0 2.4903e-01 1.1 4.38e+07 1.1 2.3e+02 
>> 4.2e+03 0.0e+00  0 42 23  1  0   0 42 23  1  0   687
>> UpdateVectors          1 1.0 4.2958e-03 1.2 4.51e+06 1.1 0.0e+00 
>> 0.0e+00 0.0e+00  0  4  0  0  0   0  4  0  0  0  4107
>> VecDot                 1 1.0 5.6815e-04 4.7 2.97e+04 1.1 0.0e+00 
>> 0.0e+00 1.0e+00  0  0  0  0  0   0  0  0  0  0   204
>> VecNorm                8 1.0 2.5260e-03 3.2 2.38e+05 1.1 0.0e+00 
>> 0.0e+00 8.0e+00  0  0  0  0  2   0  0  0  0  2   368
>> VecScale              27 1.0 5.9605e-04 1.1 4.01e+05 1.1 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0  2629
>> VecCopy               53 1.0 4.0610e-03 1.4 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> VecSet                77 1.0 6.2165e-03 1.1 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> VecAXPY               38 1.0 2.7709e-03 1.7 1.13e+06 1.1 0.0e+00 
>> 0.0e+00 0.0e+00  0  1  0  0  0   0  1  0  0  0  1592
>> VecMAXPY              38 1.0 2.5925e-02 1.1 1.13e+07 1.1 0.0e+00 
>> 0.0e+00 0.0e+00  0 11  0  0  0   0 11  0  0  0  1701
>> VecAssemblyBegin       5 1.0 9.0070e-03 2.3 0.00e+00 0.0 3.6e+01 
>> 2.1e+04 1.5e+01  0  0  4  0  3   0  0  4  0  4     0
>> VecAssemblyEnd         5 1.0 3.4809e-04 1.1 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> VecScatterBegin       73 1.0 8.5931e-03 1.5 0.00e+00 0.0 4.6e+02 
>> 8.9e+03 0.0e+00  0  0 45  2  0   0  0 45  2  0     0
>> VecScatterEnd         73 1.0 2.2542e-02 2.2 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> VecReduceArith        76 1.0 3.0838e-02 1.1 1.24e+07 1.1 0.0e+00 
>> 0.0e+00 0.0e+00  0 12  0  0  0   0 12  0  0  0  1573
>> VecReduceComm         38 1.0 4.8040e-02 2.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 3.8e+01  0  0  0  0  8   0  0  0  0 11     0
>> VecNormalize           8 1.0 2.7280e-03 2.8 3.56e+05 1.1 0.0e+00 
>> 0.0e+00 8.0e+00  0  0  0  0  2   0  0  0  0  2   511
>> MatMult               67 1.0 4.1397e-01 1.1 7.53e+07 1.1 4.0e+02 
>> 4.2e+03 0.0e+00  0 71 40  1  0   0 71 40  1  0   710
>> MatSolve              28 1.0 5.1757e+02 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00 95  0  0  0  0  95  0  0  0  0     0
>> MatLUFactorSym         1 1.0 3.6097e-04 1.1 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> MatLUFactorNum         1 1.0 1.0464e+01 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  2  0  0  0  0   2  0  0  0  0     0
>> MatAssemblyBegin       9 1.0 3.3842e-0146.7 0.00e+00 0.0 5.4e+01 
>> 6.0e+04 8.0e+00  0  0  5  2  2   0  0  5  2  2     0
>> MatAssemblyEnd         9 1.0 2.3042e-01 1.0 0.00e+00 0.0 3.6e+01 
>> 9.4e+02 3.1e+01  0  0  4  0  7   0  0  4  0  9     0
>> MatGetRow           5206 1.1 3.1164e-03 1.1 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> MatGetSubMatrice       5 1.0 8.7580e-01 1.2 0.00e+00 0.0 1.5e+02 
>> 1.1e+06 2.5e+01  0  0 15 88  6   0  0 15 88  7     0
>> MatZeroEntries         2 1.0 1.0233e-02 1.1 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> MatView                2 1.0 1.0149e-03 2.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 2.0e+00  0  0  0  0  0   0  0  0  0  1     0
>> KSPSetup               1 1.0 2.8610e-06 1.5 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0     0
>> KSPSolve              28 1.0 5.1758e+02 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 2.8e+01 95  0  0  0  6  95  0  0  0  8     0
>> PCSetUp                1 1.0 1.0467e+01 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 8.0e+00  2  0  0  0  2   2  0  0  0  2     0
>> PCApply               28 1.0 5.1757e+02 1.0 0.00e+00 0.0 0.0e+00 
>> 0.0e+00 0.0e+00 95  0  0  0  0  95  0  0  0  0     0
>> ------------------------------------------------------------------------------------------------------------------------ 
>>
>>
>> Memory usage is given in bytes:
>>
>> Object Type          Creations   Destructions   Memory  Descendants' 
>> Mem.
>>
>> --- Event Stage 0: Main Stage
>>
>>  Spectral Transform     1              1        536     0
>> Eigenproblem Solver     1              1        824     0
>>      Inner product     1              1        428     0
>>          Index Set    38             38    1796776     0
>>  IS L to G Mapping     1              1      58700     0
>>                Vec    65             65    5458584     0
>>        Vec Scatter     9              9       7092     0
>>  Application Order     1              1     155232     0
>>             Matrix    17             16   17715680     0
>>      Krylov Solver     1              1        832     0
>>     Preconditioner     1              1        744     0
>>             Viewer     2              2       1088     0
>> ======================================================================================================================== 
>>
>> Average time to get PetscTime(): 1.90735e-07
>> Average time for MPI_Barrier(): 5.9557e-05
>> Average time for zero size MPI_Send(): 2.97427e-05
>> #PETSc Option Table entries:
>> -log_summary
>> -mat_superlu_dist_parsymbfact
>> #End o PETSc Option Table entries
>> Compiled without FORTRAN kernels
>> Compiled with full precision matrices (default)
>> sizeof(short) 2 sizeof(int) 4 sizeof(long) 8 sizeof(void*) 8 
>> sizeof(PetscScalar) 8
>> Configure run at: Wed May  6 15:14:39 2009
>> Configure options: --download-superlu_dist=1 --download-parmetis=1 
>> --with-mpi-dir=/usr/lib/mpich --with-shared=0
>> -----------------------------------------
>> Libraries compiled on Wed May  6 15:14:49 CEST 2009 on medusa1
>> Machine characteristics: Linux medusa1 2.6.18-6-amd64 #1 SMP Fri Dec 
>> 12 05:49:32 UTC 2008 x86_64 GNU/Linux
>> Using PETSc directory: 
>> /home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5
>> Using PETSc arch: linux-gnu-c-debug
>> -----------------------------------------
>> Using C compiler: /usr/lib/mpich/bin/mpicc -Wall -Wwrite-strings 
>> -Wno-strict-aliasing -g3  Using Fortran compiler: 
>> /usr/lib/mpich/bin/mpif77 -Wall -Wno-unused-variable -g   
>> -----------------------------------------
>> Using include paths: 
>> -I/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/linux-gnu-c-debug/include 
>> -I/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/include 
>> -I/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/linux-gnu-c-debug/include 
>> -I/usr/lib/mpich/include  ------------------------------------------
>> Using C linker: /usr/lib/mpich/bin/mpicc -Wall -Wwrite-strings 
>> -Wno-strict-aliasing -g3
>> Using Fortran linker: /usr/lib/mpich/bin/mpif77 -Wall 
>> -Wno-unused-variable -g Using libraries: 
>> -Wl,-rpath,/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/linux-gnu-c-debug/lib 
>> -L/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/linux-gnu-c-debug/lib 
>> -lpetscts -lpetscsnes -lpetscksp -lpetscdm -lpetscmat -lpetscvec 
>> -lpetsc        -lX11 
>> -Wl,-rpath,/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/linux-gnu-c-debug/lib 
>> -L/home/fredrik/Hakan/cmlfet/external/petsc-3.0.0-p5/linux-gnu-c-debug/lib 
>> -lsuperlu_dist_2.3 -llapack -lblas -lparmetis -lmetis -lm 
>> -L/usr/lib/mpich/lib -L/usr/lib/gcc/x86_64-linux-gnu/4.1.2 
>> -L/usr/lib64 -L/lib64 -ldl -lmpich -lpthread -lrt -lgcc_s -lg2c -lm 
>> -L/usr/lib/gcc/x86_64-linux-gnu/3.4.6 -L/lib -lm -ldl -lmpich 
>> -lpthread -lrt -lgcc_s -ldl
>> ------------------------------------------
>>
>> real    9m10.616s
>> user    0m23.921s
>> sys    0m6.944s
>>
>>
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>>
>>
>> Satish Balay wrote:
>> Just a note about scalability: its a function of the hardware as
>> well.. For proper scalability studies - you'll need a true distributed
>> system with fast network [not SMP nodes..]
>>
>> Satish
>>
>> On Fri, 8 May 2009, Fredrik Bengzon wrote:
>>
>>
>> Hong,
>> Thank you for the suggestions, but I have looked at the EPS and KSP 
>> objects
>> and I can not find anything wrong. The problem is that it takes 
>> longer to
>> solve with 4 cpus than with 2 so the scalability seems to be absent 
>> when using
>> superlu_dist. I have stored my mass and stiffness matrix in the 
>> mpiaij format
>> and just passed them on to slepc. When using the petsc iterative krylov
>> solvers i see 100% workload on all processors but when i switch to
>> superlu_dist only two cpus seem to do the whole work of LU factoring. 
>> I don't
>> want to use the krylov solver though since it might cause slepc not to
>> converge.
>> Regards,
>> Fredrik
>>
>> Hong Zhang wrote:
>>
>> Run your code with '-eps_view -ksp_view' for checking
>> which methods are used
>> and '-log_summary' to see which operations dominate
>> the computation.
>>
>> You can turn on parallel symbolic factorization
>> with '-mat_superlu_dist_parsymbfact'.
>>
>> Unless you use large num of processors, symbolic factorization
>> takes ignorable execution time. The numeric
>> factorization usually dominates.
>>
>> Hong
>>
>> On Fri, 8 May 2009, Fredrik Bengzon wrote:
>>
>>
>> Hi Petsc team,
>> Sorry for posting questions not really concerning the petsc core, but 
>> when
>> I run superlu_dist from within slepc I notice that the load balance is
>> poor. It is just fine during assembly (I use Metis to partition my 
>> finite
>> element mesh) but when calling the slepc solver it dramatically 
>> changes. I
>> use superlu_dist as solver for the eigenvalue iteration. My question is:
>> can this have something to do with the fact that the option 'Parallel
>> symbolic factorization' is set to false? If so, can I change the options
>> to superlu_dist using MatSetOption for instance? Also, does this mean 
>> that
>> superlu_dist is not using parmetis to reorder the matrix?
>> Best Regards,
>> Fredrik Bengzon
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> --What most experimenters take for granted before they begin their 
>> experiments is infinitely more interesting than any results to which 
>> their experiments lead.
>> -- Norbert Wiener
>
>



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