Hello everybody,<br><br>I've coded a program which solves, in parallel, the three-dimensional Bratu problem. Afterwards, I've run tests in a cluster to see how it would go and, at first, it seemed ok to me, but then I've noticed that whenever I increased the number of processors (from 16 to 32, for example), the program started to diverge due to a failure in the Line Search Newton's Method. Here is what a monitoring function prints out:<br>
<br>nonlinear iteration number = 1, norm(F(x)) = 1013.53, linear iterations = 16<br>nonlinear iteration number = 2, norm(F(x)) = 1013.33, linear iterations = 32<br>nonlinear iteration number = 3, norm(F(x)) = 1013.33, linear iterations = 48<br>
Nonlinear solve did not converge due to DIVERGED_LS_FAILURE<br><br>Indeed, one can see that the method is really diverging (for smaller tests, though, say N = 8 * 8 * 8, it converges).<br><br>What's wrong here? Is it something with my code? If yes, how can I fix it?<br>
<br>Best regards,<br><br>Rafael<br><br>