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<div class="moz-cite-prefix">Recently I played around with some AMD
EPYC cpus and the bad thing is that I also saw some strange
numbers when using libflame/aocl 2.1.</div>
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<div class="moz-cite-prefix">The 'workaround' is probably to just
use Intel's MKL. Since version 2020 the MKL performs rather well
when using AMD cpus, however, if you want to get the best
performance you have to additionally set:<br>
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<div class="moz-cite-prefix">export MKL_DEBUG_CPU_TYPE=5<br>
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<div class="moz-cite-prefix">which gives an additional 10-20%
speedup with MKL 2020, while for earlier versions the speedup is
greater than 200%</div>
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<div class="moz-cite-prefix">Kind regards,</div>
<div class="moz-cite-prefix">Tobias</div>
<div class="moz-cite-prefix"><br>
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<div class="moz-cite-prefix">On 2/2/20 10:57 PM, Paolo Giannozzi
wrote:<br>
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<blockquote type="cite"
cite="mid:CAPMgbCsAiTK+wmcBvGxbSVLgqWpbrTnany-AO4X4cAy4j9pH1Q@mail.gmail.com">
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<div dir="ltr">On Sun, Feb 2, 2020 at 10:23 PM Evgeny Permyakov
<<a href="mailto:permeakra@gmail.com"
moz-do-not-send="true">permeakra@gmail.com</a>> wrote:</div>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div dir="ltr">sidenote: I had to set **orte_execute_quiet
= true** in ~/.openmpi/mca-params.conf so mpi didn't mess
with extra messages<br>
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</blockquote>
<div><br>
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<div>thank you for this useful piece of information: I got
rid of those annoying messages<br>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div dir="ltr">I don't use epw in my work and pwscf tests
work just fine, but the fact that some tests failed bother
me. Should I investigate it further and how? I'm not
versed in QE code, I'm a humble user.</div>
</blockquote>
<div> </div>
<div>investigating further would be a good thing, but it is
not easy: one has to figure out which piece of code fails,
then why. Even if one succeeds, very often the problem is in
the library itself and there is nothing that can be done.<br>
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<div><br>
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<div>Frequent offenders are complex-valued routines (e.g.
zdotc) that seem to follow two different incompatible
conventions, but the symptom is a hard crash, not a wrong
number. <br>
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<br clear="all">
</div>
Paolo<br>
<div>-- <br>
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<div>Paolo Giannozzi, Dip. Scienze Matematiche
Informatiche e Fisiche,<br>
Univ. Udine, via delle Scienze 208, 33100 Udine,
Italy<br>
Phone +39-0432-558216, fax +39-0432-558222<br>
<br>
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<pre class="moz-quote-pre" wrap="">_______________________________________________
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</blockquote>
<p><br>
</p>
<pre class="moz-signature" cols="72">--
M.Sc. Tobias Klöffel
=======================================================
HPC (High Performance Computing) group
Erlangen Regional Computing Center(RRZE)
Friedrich-Alexander-Universität Erlangen-Nürnberg
Martensstr. 1
91058 Erlangen
Room: 1.133
Phone: +49 (0) 9131 / 85 - 20101
=======================================================
E-mail: <a class="moz-txt-link-abbreviated" href="mailto:tobias.kloeffel@fau.de">tobias.kloeffel@fau.de</a></pre>
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