SBAIJ issue

Andreas Grassl Andreas.Grassl at
Tue Oct 13 05:00:55 CDT 2009

Barry Smith schrieb:
>   Perhaps you have done enough memory preallocation for the
> multiprocessors and it is going very--very slowly with memory allocations?

do you mean this line

MatMPISBAIJSetPreallocation(A, bs,nz, PETSC_NULL,nz, PETSC_NULL)
I set bs to 1 and nz to 77

or do you mean the icntl(14) option of MUMPS? Increasing to 2000 allows to
complete the run with np=4.

on a even larger problem (~1800000 DOF) I now get by setting the icntl(23)
option to a reasonable value a full run.

So it seems it is a MUMPS-finetuning-problem!?

The problem with -ksp_view_binary is persisting.

Is it possible that MUMPS is working much faster and load balancing better if it
has a vaste amount of memory available?

Any general advices beside switching to a larger machine?



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