On Fri, Aug 16, 2013 at 2:11 AM, Cong Li <[email protected]> wrote:
> Hi > > I am a rookie to PETSc, and I am wondering about whether I should call > MPI_Barrier to explicitly synchronize processes between PETSc calls. > For example, a piece of code like below > > ierr = MatMult(A,x,Ax); CHKERRQ(ierr); > ierr = VecWAXPY(r, neg_one, Ax, b);CHKERRQ(ierr); > > Should I add MPI_Barrier inbetween MatMult call and VecWAXPY call ? > No Matt > My guess is that it is unnecessary. However, I am not so confident in this > guess, for I don't have much experience on using PETSc. > > Thanks in advance. > > Cong Li > -- 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
