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<div class="moz-cite-prefix">On 15/3/2018 6:21 PM, Matthew Knepley
wrote:<br>
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<blockquote type="cite"
cite="mid:CAMYG4G=0x6ToqQGsm-4pmBE6GZvfh_exaPcBy4vu3pTkiQzCbw@mail.gmail.com">
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<div class="gmail_quote">On Thu, Mar 15, 2018 at 3:51 PM, TAY
wee-beng <span dir="ltr"><<a
href="mailto:zonexo@gmail.com" target="_blank"
moz-do-not-send="true">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'm running a CFD code which solves the momentum and
Poisson eqns.<br>
<br>
Due to poor scaling with HYPRE at higher cpu no., I
decided to try using PETSc with boomeramg and gamg.<br>
<br>
I tested for some small cases and it work well. However,
for the large problem which has poor scaling, it gives an
error when I change my Poisson solver from pure HYPRE to
PETSc with boomeramg and gamg.<br>
<br>
The error is :<br>
<br>
Caught signal number 11 SEGV: Segmentation Violation,
probably memory access out of range<br>
<br>
I tried using:<br>
<br>
-poisson_ksp_type richardson -poisson_pc_type hypre
-poisson_pc_type_hypre boomeramg<br>
<br>
-poisson_ksp_type gmres -poisson_pc_type hypre
-poisson_pc_type_hypre boomeramg<br>
<br>
-poisson_pc_type gamg -poisson_pc_gamg_agg_nsmooths 1<br>
<br>
but they all gave similar error.<br>
<br>
So why is this so? How should I troubleshoot? I am now
running a debug ver of PETSc to check the error msg.</blockquote>
<div><br>
</div>
<div>1) For anything like this, we would like to see a stack
trace from the debugger or valgrind output.</div>
<div><br>
</div>
<div>2) We do have several Poisson examples. Does it fail
for you on those?</div>
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</blockquote>
Hi,<br>
<br>
Can you recommend me some suitable egs? Esp in Fortran?<br>
<blockquote type="cite"
cite="mid:CAMYG4G=0x6ToqQGsm-4pmBE6GZvfh_exaPcBy4vu3pTkiQzCbw@mail.gmail.com">
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<div>3) You can also try ML, which is the same type of MG as
GAMG. (--download-ml).</div>
<div><br>
</div>
</div>
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</blockquote>
My cluster can't connect to the internet. Where can I 1st download
it?<br>
<br>
Similarly, how can I find out the location of the ext software by
myself?<br>
<blockquote type="cite"
cite="mid:CAMYG4G=0x6ToqQGsm-4pmBE6GZvfh_exaPcBy4vu3pTkiQzCbw@mail.gmail.com">
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<div> Thanks,</div>
<div><br>
</div>
<div> Matt</div>
<div> </div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex"><span
class="HOEnZb"><font color="#888888"><br>
-- <br>
Thank you very much.<br>
<br>
Yours sincerely,<br>
<br>
==============================<wbr>==================<br>
TAY Wee-Beng (Zheng Weiming) 郑伟明<br>
Personal research webpage: <a
href="http://tayweebeng.wixsite.com/website"
rel="noreferrer" target="_blank"
moz-do-not-send="true">http://tayweebeng.wixsite.com/<wbr>website</a><br>
Youtube research showcase: <a
href="https://www.youtube.com/channel/UC72ZHtvQNMpNs2uRTSToiLA"
rel="noreferrer" target="_blank"
moz-do-not-send="true">https://www.youtube.com/channe<wbr>l/UC72ZHtvQNMpNs2uRTSToiLA</a><br>
linkedin: <a
href="http://www.linkedin.com/in/tay-weebeng"
rel="noreferrer" target="_blank"
moz-do-not-send="true">www.linkedin.com/in/tay-weeben<wbr>g</a><br>
==============================<wbr>==================<br>
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-- <br>
<div class="gmail_signature" data-smartmail="gmail_signature">
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<div>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><br>
</div>
<div><a href="http://www.caam.rice.edu/%7Emk51/"
target="_blank" moz-do-not-send="true">https://www.cse.buffalo.edu/~knepley/</a><br>
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