petsc-users Digest, Vol 2, Issue 32

STEPHANE TCHOUANMO tchouanm at msn.com
Tue Feb 24 12:17:27 CST 2009


Here is my -log_summary:
Something looks a bit strange to me; its the MPI Reductions below.
Other than that, i dont see anything relevant.
What do you think?
Thanks



---------------------------------------------- PETSc Performance Summary: ----------------------------------------------

./diff-conv-opt on a linux-gnu named linux-stchouan with 1 processor, by stephane Tue Feb 24 13:54:35 2009
Using Petsc Release Version 2.3.3, Patch 13, Thu May 15 17:29:26 CDT 2008 HG revision: 4466c6289a0922df26e20626fd4a0b4dd03c8124

                                                  Max       Max/Min        Avg      Total 
Time (sec):                         2.937e+03      1.00000   2.937e+03
Objects:                              3.420e+03      1.00000   3.420e+03
Flops:                                  2.690e+09      1.00000   2.690e+09  2.690e+09
Flops/sec:                           9.161e+05      1.00000   9.161e+05  9.161e+05
MPI Messages:                  0.000e+00      0.00000   0.000e+00  0.000e+00
MPI Message Lengths:    0.000e+00      0.00000   0.000e+00  0.000e+00
MPI Reductions:                1.189e+05      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: 2.9367e+03 100.0%  2.6905e+09 100.0%  0.000e+00   0.0%  0.000e+00        0.0%  1.106e+03   0.9% 

------------------------------------------------------------------------------------------------------------------------
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/sec: 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)
------------------------------------------------------------------------------------------------------------------------

Event                Count      Time (sec)     Flops/sec                         --- 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

VecDot               202 1.0 3.0360e-02 1.0 3.96e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0   396
VecMDot              202 1.0 3.0552e-02 1.0 3.94e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0   394
VecNorm             1110 1.0 1.2257e+00 1.0 5.40e+07 1.0 0.0e+00 0.0e+00 0.0e+00  0  2  0  0  0   0  2  0  0  0    54
VecScale             404 1.0 3.5342e-02 1.0 3.41e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0   341
VecCopy              507 1.0 8.4626e-02 1.0 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              1408 1.0 1.1664e-01 1.0 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              202 1.0 2.6221e-02 1.0 4.59e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0   459
VecWAXPY             202 1.0 4.4239e-02 1.0 1.36e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  0  0  0  0   0  0  0  0  0   136
VecMAXPY             404 1.0 7.3515e-02 1.0 3.27e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  1  0  0  0   0  1  0  0  0   327
VecAssemblyBegin     302 1.0 9.2960e-04 1.0 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
VecAssemblyEnd       302 1.0 5.5790e-04 1.0 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      603 1.0 1.9933e-01 1.0 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
VecNormalize         404 1.0 5.5408e-01 1.0 6.52e+07 1.0 0.0e+00 0.0e+00 0.0e+00  0  1  0  0  0   0  1  0  0  0    65
MatMult              404 1.0 2.6457e+00 1.0 2.26e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0 22  0  0  0   0 22  0  0  0   226
MatSolve             404 1.0 4.6454e+00 1.0 1.28e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0 22  0  0  0   0 22  0  0  0   128
MatLUFactorNum       202 1.0 1.5211e+01 1.0 8.85e+07 1.0 0.0e+00 0.0e+00 0.0e+00  1 50  0  0  0   1 50  0  0  0    89
MatILUFactorSym      100 1.0 1.9993e+00 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 1.0e+02  0  0  0  0  0   0  0  0  0  9     0
MatAssemblyBegin     404 1.0 9.6217e-04 1.0 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
MatAssemblyEnd       404 1.0 1.4601e+00 1.0 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
MatGetRowIJ          100 1.0 2.4641e-04 1.0 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
MatGetOrdering       100 1.0 7.6755e-02 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 2.0e+02  0  0  0  0  0   0  0  0  0 18     0
MatZeroEntries        99 1.0 3.6160e-01 1.0 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
SNESSolve            100 1.0 2.9339e+03 1.0 9.17e+05 1.0 0.0e+00 0.0e+00 1.0e+03100100  0  0  1 100100  0  0 91     1
SNESLineSearch       202 1.0 7.9707e+02 1.0 4.35e+05 1.0 0.0e+00 0.0e+00 4.0e+02 27 13  0  0  0  27 13  0  0 37     0
SNESFunctionEval     302 1.0 1.1836e+03 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 3.0e+02 40  0  0  0  0  40  0  0  0 27     0
SNESJacobianEval     202 1.0 1.7238e+03 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 2.0e+02 59  0  0  0  0  59  0  0  0 18     0
KSPGMRESOrthog       202 1.0 7.0303e-02 1.0 3.42e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0  1  0  0  0   0  1  0  0  0   342
KSPSetup             202 1.0 4.6391e-02 1.0 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             202 1.0 2.4101e+01 1.0 9.65e+07 1.0 0.0e+00 0.0e+00 3.0e+02  1 86  0  0  0   1 86  0  0 27    97
PCSetUp              202 1.0 1.7296e+01 1.0 7.78e+07 1.0 0.0e+00 0.0e+00 3.0e+02  1 50  0  0  0   1 50  0  0 27    78
PCApply              404 1.0 4.6487e+00 1.0 1.28e+08 1.0 0.0e+00 0.0e+00 0.0e+00  0 22  0  0  0   0 22  0  0  0   128
------------------------------------------------------------------------------------------------------------------------

Memory usage is given in bytes:

Object Type          Creations   Destructions   Memory  Descendants' Mem.

--- Event Stage 0: Main Stage

           Index Set   904            901   107564984     0
                 Vec     1511           1497  357441684     0
         Vec Scatter   604          604          0     0
              Matrix       101          99     942432084     0
                SNES   100              99      12276     0
       Krylov Solver   100        99    1671120     0
      Preconditioner   100        99      14256     0
========================================================================================================================
Average time to get PetscTime(): 1.49164e-06
OptionTable: -snes_converged_reason
OptionTable: -snes_max_it 20
OptionTable: -snes_rtol 0.0000001
OptionTable: -snes_stol 0.001
Compiled without FORTRAN kernels
Compiled with full precision matrices (default)
sizeof(short) 2 sizeof(int) 4 sizeof(long) 4 sizeof(void*) 4 sizeof(PetscScalar) 8
Configure run at: Mon Feb 23 23:01:43 2009
Configure options: --with-debugging=no -with-shared --download-mpich=1
-----------------------------------------




> 
> Message: 7
> Date: Tue, 24 Feb 2009 18:05:38 +0100
> From: STEPHANE TCHOUANMO <tchouanm at msn.com>
> Subject: Petsc slowness on a single processor machine?
> To: <petsc-users at mcs.anl.gov>
> Message-ID: <BAY107-W5D076FE1F3A7037240F88C2AF0 at phx.gbl>
> Content-Type: text/plain; charset="windows-1256"
> 
> 
> Dear all,
> 
> I use petsc to solve a nonlinear convection-diffusion type equation in porous media.
> The built linear system's size is 30000 and its resolution lasts about a hour on a single processor machine (my laptop...).
> I
> run for that a hundred time steps and have in average 4 Newton
> iterations per time step. So a hour seems huge to me with the optimized
> version of Petsc.
> I tryed to profile my code with the options
> "-log_summary" and "-info". What i get out of it is that the first time
> step lasts about 15min representing 25% of the total time and i think
> its not normal.
> The thing is, these 15min happen at the second call
> of the petsc routine "VecScatterCreate()" right after the first Newton residual.
> 
> Any idea?
> Thanks.
> 
> Stephane
> 
> 
> 
> _________________________________________________________________
> Show them the way! Add maps and directions to your party invites. 
> http://www.microsoft.com/windows/windowslive/products/events.aspx
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20090224/c695a2bf/attachment-0001.htm>
> 
> ------------------------------
> 
> Message: 8
> Date: Tue, 24 Feb 2009 11:22:18 -0600
> From: Matthew Knepley <knepley at gmail.com>
> Subject: Re: Petsc slowness on a single processor machine?
> To: PETSc users list <petsc-users at mcs.anl.gov>
> Message-ID:
> 	<a9f269830902240922y6751b40aqf8ea84257c139fd9 at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> 2009/2/24 STEPHANE TCHOUANMO <tchouanm at msn.com>
> 
> >  Dear all,
> >
> > I use petsc to solve a nonlinear convection-diffusion type equation in
> > porous media.
> > The built linear system's size is 30000 and its resolution lasts about a
> > hour on a single processor machine (my laptop...).
> > I run for that a hundred time steps and have in average 4 Newton iterations
> > per time step. So a hour seems huge to me with the optimized version of
> > Petsc.
> > I tryed to profile my code with the options "-log_summary" and "-info".
> > What i get out of it is that the first time step lasts about 15min
> > representing 25% of the total time and i think its not normal.
> > The thing is, these 15min happen at the second call of the petsc routine
> > "VecScatterCreate()" right after the first Newton residual.
> >
> 
> We can't say anything without seeing the entire output of -log_summary.
> 
>    Matt
> 
> 
> >
> > Any idea?
> > Thanks.
> >
> > Stephane
> >
> > <http://www.live.com/getstarted.aspx>
> > <http://www.microsoft.com/windows/windowslive/default.aspx>
> > ------------------------------
> > See all the ways you can stay connected to friends and family<http://www.microsoft.com/windows/windowslive/default.aspx>
> >
> 
> 
> 
> -- 
> 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
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20090224/cd1ffccb/attachment-0001.htm>
> 
> ------------------------------
> 
> _______________________________________________
> petsc-users mailing list
> petsc-users at mcs.anl.gov
> https://lists.mcs.anl.gov/mailman/listinfo/petsc-users
> 
> 
> End of petsc-users Digest, Vol 2, Issue 32
> ******************************************

_________________________________________________________________
News, entertainment and everything you care about at Live.com. Get it now!
http://www.live.com/getstarted.aspx
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20090224/f3c06de3/attachment.htm>


More information about the petsc-users mailing list