Distinguished PETSc experts, Assuming processor k has defined N entries of a parallel matrix using MatSetValues. The half of the entries are in matrix rows belonging to this processor, but the other half are situated in rows of other processors.
My question: When does MatAssemblyBegin+MatAssemblyEnd take longer, if the rows where the second half of the entries are situated belong all to one single other processor, e.g. processor k+1, or if these rows are distributed across several, let's say 4, other processors? Is there a significant difference? Thanks in advance for your answer, Trini
