On Thu, May 26, 2011 at 13:46, Bart?omiej W <bartlomiej.wach at yahoo.pl>wrote:
> That helped. > > I am also wondering about SEQ and MPI matrices, do they differ more than > just in way of allocating data? When I run a small problem on 2 processes on > single machine, it slows down greatly if I use > > > MatCreateMPIAIJ(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,n,n,5,PETSC_NULL,5,PETSC_NULL,&L); > > As I get mallocs during mat assembly while o_nz and d_nz are set to 5 where > 5 is max nonzeros per whole row. I also get stash:0 assuring that values are > set by correct process. Your preallocation is either incorrect or it is getting lost. Try MAT_NEW_NONZERO_ALLOCATION_ERR http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-dev/docs/manualpages/Mat/MatSetOption.html -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20110526/5ca7882f/attachment.htm>
