[petsc-users] the size of matrix in PETSc solver

[Barry Smith]

On Dec 31, 2010, at 12:28 PM, Matthew Knepley wrote:

> On Fri, Dec 31, 2010 at 12:23 PM, Peter Wang <pengxwang at hotmail.com> wrote:
> I am trying to build a big matrix to be solved by KSP.  I am wondering is there any limitation to the matrix size? What is the maximum size of the matrix in KSP? For example, if a 100 M by 100 M matrix can be handled by the KSP? Thanks a lot.
> 
> There are two limitations:
> 
>   a) Machine memory. To combat this, we recommend running in parallel
> 
>   b) Representation of row/col numbers by integers. If you have > 2B rows, you will need to reconfigure
>      using --with-64-bit-ints.

--with-64-bit-indices

> 
>   Thanks,
> 
>      Matt
> 
> -- 
> What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.
> -- Norbert Wiener