matrix assembling time

[Barry Smith]

    Run the same job with -info and send the results to petsc-maint at mcs.anl.gov


On Mar 6, 2009, at 12:50 PM, Yixun Liu wrote:

> Hi,
> Using PETSc the assembling time for a mesh with 6000 vertices  is  
> about
> 14 second parallelized on 4 processors, but another sequential program
> based on gmm lib is about 0.6 second. PETSc's solver is much faster  
> than
> gmm, but I don't know why its assembling is so slow although I have
> preallocate an enough space for the matrix.
>
> MatMPIAIJSetPreallocation(sparseMeshMechanicalStiffnessMatrix, 1000,
> PETSC_NULL, 1000, PETSC_NULL);
>
> Yixun
>