the size of matrix in PETSc solver
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.
On Fri, Dec 31, 2010 at 12:23 PM, Peter Wang <[email protected]> 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. 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
On Dec 31, 2010, at 12:28 PM, Matthew Knepley wrote:
On Fri, Dec 31, 2010 at 12:23 PM, Peter Wang <[email protected]> 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
participants (3)
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Barry Smith -
Matthew Knepley -
Peter Wang