Just pass it as a command line option. It gives profiling output in PetscFinalize().<div class="gmail_extra"><br><br><div class="gmail_quote">On Sat, Nov 3, 2012 at 10:52 AM, w_ang_temp <span dir="ltr"><<a href="mailto:w_ang_temp@163.com" target="_blank">w_ang_temp@163.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="line-height:1.7;font-size:14px;font-family:arial"><div>Is there something that need attention when setting up PETSc? The -log_summary<br>
is no use in my system.<br><br><br></div><div class="im">>At 2012-11-03 23:31:52,"Jed Brown" <<a href="mailto:jedbrown@mcs.anl.gov" target="_blank">jedbrown@mcs.anl.gov</a>> wrote:<br>
</div><blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex"><div class="im">>1. <b>Always</b> send -log_summary when asking about performance.
<div>>2. AMG setup costs more, the solve should be faster, especially for large problems.</div>
<div>>3. 30k degrees of freedom is not large.</div>
</div><div class="gmail_extra"><br><br>
<div class="gmail_quote"><div class="im">>>On Sat, Nov 3, 2012 at 10:27 AM, w_ang_temp <span dir="ltr"><<a href="mailto:w_ang_temp@163.com" target="_blank">w_ang_temp@163.com</a>></span> wrote:<br>
</div><blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
<div style="LINE-HEIGHT:1.7;FONT-FAMILY:arial;FONT-SIZE:14px"><div class="im">
<div>>>Hello,</div>
<div>>> I have tried AMG, but there are some problems. I use the command:<br>>> mpiexec -n 4 ./ex4f -ksp_type gmres -pc_type gamg -pc_gamg_agg_nsmooths 1 -ksp_gmres_restart 170 -ksp_rtol 1.0e-15 ->>ksp_converged_reason.<br>
>> The matrix has a size of 30000. However, compared with -pc_type asm,<br>>>the amg need more time:asm needs 4.9s, amg needs 13.7s. I did several tests<br>>>and got the same conclusion. When it begins, the screen shows the information: <br>
>>[0]PCSetData_AGG bs=1 MM=7601. I do not know the meaning. And if there is some<br>>>parameters that affect the performance of AMG?<br>>> Besides, I want to confirm a conception. In my view, AMG itself can be a solver<br>
>>like gmres. It can also be used as a preconditioner like jacobi and is used by combining<br>>>with other solver. Is it right? If it is right, how use AMG solver?<br>>> My codes are attached.<br>>> Thanks.<br>
>> Jim</div>
<div><br><br> </div></div><div class="im">>At 2012-11-01 22:00:28,"Jed Brown" <<a href="mailto:jedbrown@mcs.anl.gov" target="_blank">jedbrown@mcs.anl.gov</a>> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex">
<div class="gmail_extra">>Yes, it's faster to understand this error message than to have "mysteriously slow performance".</div>
<div class="gmail_extra"><br></div>
<div class="gmail_extra">><em>* Preallocation routines now automatically set MAT_NEW_NONZERO_ALLOCATION_ERR, if you intentionally preallocate less than necessary then </em>><em>use MatSetOption(mat,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE) to disable the error generation.<br>
</em><br>><a href="http://www.mcs.anl.gov/petsc/documentation/changes/33.html" target="_blank">http://www.mcs.anl.gov/petsc/documentation/changes/33.html</a><br><br>
<div class="gmail_quote">>On Thu, Nov 1, 2012 at 8:57 AM, w_ang_temp <span dir="ltr"><<a href="mailto:w_ang_temp@163.com" target="_blank">w_ang_temp@163.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:rgb(204,204,204) 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
<div>>Do you mean that the two versions have a different in this point? If I use the new version, I have to</div>
<div>>make some modifications on my codes?</div></blockquote></div><br></div></blockquote></div></div><br><br><span title="neteasefooter"><span></span></span></blockquote></div><br></div></blockquote></div><br><br><span title="neteasefooter"><span></span></span></blockquote>
</div><br></div>