New approach for external direct solvers in PETSc

[Lisandro Dalcin]

On Thu, Aug 7, 2008 at 5:05 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>>
>   After a (tiny) bit more thought I think we really should make this change:

Well, very good news!

> cons
> 1) requires a large reorganization of the Mat code (will introduce bugs)
> 2) requires the user to deal with one more PETSc object (MatFactor)
>     But since most users deal with SNES/KSP/PC most users will
>     never see this new object.

Regarding (1) I believe we will end-up with a code having less bugs
than the current one.

Regarding (2), even in the case a user wants to handle by himself the
factorizations outside of KSP/PC, the new object will be not too hard
to use, as it user interface will be not too large.

>  The question is when/how to make this massive change. It is as big
> or bigger than the change I already made with MatGetFactor().
>

Well, we can start this in a separate branch. And I'll definitively
help you with all this.






>>
>> On Fri, Jul 25, 2008 at 7:02 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>>>
>>>  petsc-dev users,
>>>
>>>   I have finally completed my changes to PETSc for a new approach to
>>> accessing external direct solvers
>>> in PETSc like Spooles, MUMPS etc. I will be pushing it to petsc-dev
>>> sometime
>>> the middle of next week.
>>> If you are using the direct solvers you might consider cloning from
>>>
>>> http://petsc.cs.iit.edu/hg/petsc/petsc-dev-new-solvers  or
>>>
>>> ssh://petsc@petsc.cs.iit.edu//hg/petsc/petsc-dev-new-solvers
>>>
>>> and trying it out before then. Please report problem to
>>> petsc-maint at mcs.anl.gov as you hit them.
>>>
>>>
>>>  Barry
>>>
>>> From the changes file
>>>
>>> The "parallel direct solver" matrix types like
>>> MATAIJSPOOLES are ALL gone. Now you use -pc_factor_mat_solver_package
>>> spooles etc or PCFactorSetMatSolverPackage() or if working directly with
>>> matrices, MatGetFactor(A,MATSPOOLES,...)
>>>
>>>
>>
>>
>>
>> --
>> Lisandro Dalcín
>> ---------------
>> Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
>> Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
>> Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
>> PTLC - Güemes 3450, (3000) Santa Fe, Argentina
>> Tel/Fax: +54-(0)342-451.1594
>>
>
>



-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
PTLC - Güemes 3450, (3000) Santa Fe, Argentina
Tel/Fax: +54-(0)342-451.1594