<div class="gmail_quote">On Wed, Dec 7, 2011 at 06:31, Bogdan Dita <span dir="ltr"><<a href="mailto:bogdan@lmn.pub.ro">bogdan@lmn.pub.ro</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div id=":1i8">A few weeks ago i posted a question regarding a problem with the<br>
optimised version of PETSc, what i mean is that I obtained a higher<br>
solving time with the optimised version then with the debug<br>
version(~10-15% higher).</div></blockquote></div><br><div>What do you get from 'mpicc -show'?</div><div><br></div><div>MPICH2 has a tendency to put optimization flags into the wrappers. It's possible that the "optimized" build of PETSc is effectively using -O2 (from MPICH2) and -g3 (from PETSc with-debugging=1), which might be faster than -O2 (from MPICH2) -O (from PETSc with-debugging=0, taking precedence) that you get when you. You can use PETSc's --COPTFLAGS to set your own optimization flags for PETSc.</div>
<div><br></div><div>Let us know if this works.</div>