I finally got a chance to get back to this problem.
I played around with the different orderings available in petsc,
-pc_factor_mat_ordering_type, and Quotient Minimum Degree seemed to do the
trick. I am able to solve the system with about 7.5 GB of memory footprint in
about 4.5 minutes, where
Ok. Just so that I understand your point: you are saying that because petsc
(and other advanced direct solvers) will calculate a new ordering for the
matrix factorization, it does not help to calculate it in advance. However, for
a more basic direct solver, which does not calculate the reorderi
> On Feb 6, 2015, at 9:40 PM, Jed Brown wrote:
>
> Manav Bhatia writes:
>> I am not sure if I understand your point. Are you saying that using a
>> fill-reducing ordering for the dofs would not change the performance
>> of a direct solver?
>
> Correct. The solver is already computing an order
> On Feb 6, 2015, at 9:29 PM, Jed Brown wrote:
>
> Manav Bhatia writes:
>
>> I am in agreement with that. However my situation is more rudimentary than
>> that.
>>
>> If I run the same problem in ABAQUS, it uses a multifraontal direct solver
>> and gets done in two minutes.
>>
>> If I u
I am in agreement with that. However my situation is more rudimentary than
that.
If I run the same problem in ABAQUS, it uses a multifraontal direct solver and
gets done in two minutes.
If I use the -ksp_type preonly -pc_type lu on my code built on libmesh and
petsc, it takes ~16GB in storag
I'm not sure why MUMPS wouldn't be available on your machine, it works fine
for me (I just use the --download-mumps option when configuring PETSc).
But you seem to be suggesting that MUMPS has a builtin fill-reduction
> algorithm. Correct?
>
Yes, have a look at ICNTL(7) in the MUMPS manual. It p
It sounds like you're right at the limit of what your computer can handle
with a direct solver. Which direct solver are you using? I generally use
MUMPS or SuperLU instead of PETSc's built in direct solver (e.g. -ksp_type
preonly -pc_type lu -pc_factor_mat_solver_package superlu_dist). I think
Supe
I tried the MUMPS option through petsc using this set of options:
-ksp_type preonly -pc_type lu -pc_factor_mat_solver_package mumps
-mat_mumps_icntl_ 22 1 -mat_mumps_icntl_ 23 1
However, MUMPS does not seems to be running on my machine with the PETSC build.
I build 3.5.3 today with the do
