2009/2/24 STEPHANE TCHOUANMO <span dir="ltr"><<a href="mailto:tchouanm@msn.com">tchouanm@msn.com</a>></span><br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div>
Dear all,<br><br>I use petsc to solve a nonlinear convection-diffusion type equation in porous media.<br>The built linear system's size is 30000 and its resolution lasts about a hour on a single processor machine (my laptop...).<br>
I
run for that a hundred time steps and have in average 4 Newton
iterations per time step. So a hour seems huge to me with the optimized
version of Petsc.<br>I tryed to profile my code with the options
"-log_summary" and "-info". What i get out of it is that the first time
step lasts about 15min representing 25% of the total time and i think
its not normal.<br>The thing is, these 15min happen at the second call
of the petsc routine "VecScatterCreate()" right after the first Newton residual.</div></blockquote><div><br>We can't say anything without seeing the entire output of -log_summary.<br><br> Matt<br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div><br>Any idea?<br>Thanks.<br><br>Stephane<br><a href="http://www.live.com/getstarted.aspx" target="_blank"><br></a><a href="http://www.microsoft.com/windows/windowslive/default.aspx" target="_blank"><br></a><br><hr>See all the ways you can stay connected <a href="http://www.microsoft.com/windows/windowslive/default.aspx" target="_blank">to friends and family</a></div>
</blockquote></div><br><br clear="all"><br>-- <br>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener<br>