[petsc-dev] Can MATAIJ support block size?

Fande Kong fdkong.jd at gmail.com
Thu Sep 20 16:29:10 CDT 2018


Thanks Barry,

I am going to take a try.

Fande,

On Thu, Sep 20, 2018 at 2:15 PM Smith, Barry F. <bsmith at mcs.anl.gov> wrote:

>
>   Not a priority for us but if you implement clean code to do this we're
> likely to accept it.
>
>    Barry
>
>
> > On Sep 20, 2018, at 12:27 PM, Fande Kong <fdkong.jd at gmail.com> wrote:
> >
> > Hi Developers,
> >
> > MATBAIJ actually assumes that the point-block is dense. It is fine if
> the block size is small for example less than 50, but we may suffer from a
> memory issue if the block is large such as 1000. The block is not necessary
> dense. In my application, neutron transport equations, the block is
> actually sparse (coming from direction and energy grids).  Now I am using
> MATAIJ, but I want to take into consideration there are many variables on
> each spatial grid when doing some ILU(0).  ILU(0) is used as a subdomain
> solver for ASM and BJACOBI.
> >
> > I would like to support point-block ILU(0) in MATAIJ (not MATBAIJ)
> because the block is sparse. Any comments? It is worthwhile to do that? I
> think we might reduce the symbolic factor time when considering the block.
> >
> > Thanks,
> >
> > Fande,
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20180920/d6358095/attachment.html>


More information about the petsc-dev mailing list