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Hi,<br>
<br>
I tried valgrind in MPI but it aborts very early, with the error msg
regarding PETSc initialize.<br>
<br>
I retry again, using a lower resolution.<br>
<br>
GAMG works, but BoomerAMG and hypre doesn't. Increasing cpu too
high (80) also cause it to hang. 60 works fine.<br>
<br>
My grid size is 98x169x169<br>
<br>
But when I increase the resolution, GAMG can't work again.<br>
<br>
I tried to increase the cpu no but it still doesn't work.<br>
<br>
Previously, using single z direction partition, it work using GAMG
and hypre. So what could be the problem?<br>
<pre class="moz-signature" cols="72">Thank you.
Yours sincerely,
TAY wee-beng</pre>
<div class="moz-cite-prefix">On 25/12/2015 12:33 AM, Matthew Knepley
wrote:<br>
</div>
<blockquote
cite="mid:CAMYG4GkqJQxb=RZRRM0Lv25KDsyGBTfV9cRE40Xit-HrfXP1DA@mail.gmail.com"
type="cite">
<div dir="ltr">It sounds like you have memory corruption in a
different part of the code. Run in valgrind.
<div><br>
</div>
<div> Matt</div>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Thu, Dec 24, 2015 at 10:14 AM, TAY
wee-beng <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:zonexo@gmail.com" target="_blank">zonexo@gmail.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">Hi,<br>
<br>
I have this strange error. I converted my CFD code from a z
directon only partition to the yz direction partition. The
code works fine but when I increase the cpu no, strange
things happen when solving the Poisson eqn.<br>
<br>
I increase cpu no from 24 to 40.<br>
<br>
Sometimes it works, sometimes it doesn't. When it doesn't,
it just hangs there with no output, or it gives the error
below:<br>
<br>
Using MPI_Barrier during debug shows that it hangs at<br>
<br>
call KSPSolve(ksp,b_rhs,xx,ierr).<br>
<br>
I use hypre BoomerAMG and GAMG
(-poisson_pc_gamg_agg_nsmooths 1 -poisson_pc_type gamg)<br>
<br>
<br>
Why is this so random? Also how do I debug this type of
problem.<br>
<br>
<br>
[32]PETSC ERROR:
------------------------------------------------------------------------<br>
[32]PETSC ERROR: Caught signal number 11 SEGV: Segmentation
Violation, probably memory access out of range<br>
[32]PETSC ERROR: Try option -start_in_debugger or
-on_error_attach_debugger<br>
[32]PETSC ERROR: or see <a moz-do-not-send="true"
href="http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind"
rel="noreferrer" target="_blank">http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind</a><br>
[32]PETSC ERROR: or try <a moz-do-not-send="true"
href="http://valgrind.org" rel="noreferrer"
target="_blank">http://valgrind.org</a> on GNU/linux and
Apple Mac OS X to find memory corruption errors<br>
[32]PETSC ERROR: likely location of problem given in stack
below<br>
[32]PETSC ERROR: --------------------- Stack Frames
------------------------------------<br>
[32]PETSC ERROR: Note: The EXACT line numbers in the stack
are not available,<br>
[32]PETSC ERROR: INSTEAD the line number of the start
of the function<br>
[32]PETSC ERROR: is given.<br>
[32]PETSC ERROR: [32] HYPRE_SetupXXX line 174
/home/wtay/Codes/petsc-3.6.2/src/ksp/pc/impls/hypre/hypre.c<br>
[32]PETSC ERROR: [32] PCSetUp_HYPRE line 122
/home/wtay/Codes/petsc-3.6.2/src/ksp/pc/impls/hypre/hypre.c<br>
[32]PETSC ERROR: [32] PCSetUp line 945
/home/wtay/Codes/petsc-3.6.2/src/ksp/pc/interface/precon.c<br>
[32]PETSC ERROR: [32] KSPSetUp line 247
/home/wtay/Codes/petsc-3.6.2/src/ksp/ksp/interface/itfunc.c<br>
[32]PETSC ERROR: [32] KSPSolve line 510
/home/wtay/Codes/petsc-3.6.2/src/ksp/ksp/interface/itfunc.c<br>
[32]PETSC ERROR: --------------------- Error Message
--------------------------------------------------------------<br>
[32]PETSC ERROR: Signal received<br>
[32]PETSC ERROR: See <a moz-do-not-send="true"
href="http://www.mcs.anl.gov/petsc/documentation/faq.html"
rel="noreferrer" target="_blank">http://www.mcs.anl.gov/petsc/documentation/faq.html</a>
for trouble shooting.<br>
[32]PETSC ERROR: Petsc Release Version 3.6.2, Oct, 02, 2015<br>
[32]PETSC ERROR: ./a.out on a petsc-3.6.2_shared_gnu_debug
named n12-40 by wtay Thu Dec 24 17:01:51 2015<br>
[32]PETSC ERROR: Configure options
--with-mpi-dir=/opt/ud/openmpi-1.8.8/
--download-fblaslapack=1 --with-debugging=1
--download-hypre=1
--prefix=/home/wtay/Lib/petsc-3.6.2_shared_gnu_debug
--known-mpi-shared=1 --with-shared-libraries
--with-fortran-interfaces=1<br>
[32]PETSC ERROR: #1 User provided function() line 0 in
unknown file<br>
--------------------------------------------------------------------------<br>
MPI_ABORT was invoked on rank 32 in communicator
MPI_COMM_WORLD<br>
with errorcode 59.<span class="HOEnZb"><font color="#888888"><br>
<br>
-- <br>
Thank you.<br>
<br>
Yours sincerely,<br>
<br>
TAY wee-beng<br>
<br>
</font></span></blockquote>
</div>
<br>
<br clear="all">
<div><br>
</div>
-- <br>
<div class="gmail_signature">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</div>
</div>
</blockquote>
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