<div>Hi,</div>
<div> </div>
<div>I've tried to use log_summary but nothing came out? Did I miss out something? It worked when I used -info...<br><br> </div>
<div><span class="gmail_quote">On 2/9/07, <b class="gmail_sendername">Lisandro Dalcin</b> <<a href="mailto:dalcinl@gmail.com">dalcinl@gmail.com</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">On 2/8/07, Ben Tay <<a href="mailto:zonexo@gmail.com">zonexo@gmail.com</a>> wrote:<br>> i'm trying to solve my cfd code using PETSc in parallel. Besides the linear
<br>> eqns for PETSc, other parts of the code has also been parallelized using<br>> MPI.<br><br>Finite elements or finite differences, or what?<br><br>> however i find that the parallel version of the code running on 4 processors
<br>> is even slower than the sequential version.<br><br>Can you monitor the convergence and iteration count of momentum and<br>poisson steps?<br><br><br>> in order to find out why, i've used the -info option to print out the
<br>> details. there are 2 linear equations being solved - momentum and poisson.<br>> the momentum one is twice the size of the poisson. it is shown below:<br><br>Can you use -log_summary command line option and send the output attached?
<br><br>> i saw some statements stating "seq". am i running in sequential or parallel<br>> mode? have i preallocated too much space?<br><br>It seems you are running in parallel. The "Seq" are related to local,
<br>internal objects. In PETSc, parallel matrices have inner sequential<br>matrices.<br><br>> lastly, if Ax=b, A_sta and A_end from MatGetOwnershipRange and b_sta and<br>> b_end from VecGetOwnershipRange should always be the same value, right?
<br><br>I should. If not, you are likely going to get an runtime error.<br><br>Regards,<br><br>--<br>Lisandro Dalcín<br>---------------<br>Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)<br>Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
<br>Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)<br>PTLC - Güemes 3450, (3000) Santa Fe, Argentina<br>Tel/Fax: +54-(0)342-451.1594<br><br></blockquote></div><br>