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Hi Daniel
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<div class="">Whilst k-point parallelisation is not implemented in pw2wannier90, FFT grid parallelisation is. The latter should provide a speedup for a large supercell (which I’d normally expect to have few k-points but a large FFT grid).</div>
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<div class="">As an aside, we do ask that everyone signs with their full name and affiliation on posts to this forum.</div>
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<div class="">Best wishes,</div>
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<div class="">Arash<br class="">
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<div>— <br class="">
Professor Arash Mostofi — <a href="http://www.mostofigroup.org" class="">www.mostofigroup.org</a><br class="">
Director, Thomas Young Centre @Imperial<br class="">
Imperial College London</div>
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<div class="">On 16 Nov 2020, at 19:07, Daniel Marchand <<a href="mailto:t-dmarchand@microsoft.com" class="">t-dmarchand@microsoft.com</a>> wrote:</div>
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Hi Everyone,<o:p class=""></o:p></div>
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We’re having some trouble running pw2wannier on a very large system as it is running very slow. To give some comparison, we are able to finish the nscf calculation in ~4hours, while pw2wannier has not finished the first MMN: iknum step even after ~8 hours of
runtime. It seems like in theory pw2wannier should be parallelizable but we found poor performance beyond a single node.<o:p class=""></o:p></div>
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Is there anything we can do to help speed up the process? Parallelization steps to try out or common pitfalls that we could avoid?<o:p class=""></o:p></div>
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<o:p class=""> </o:p></div>
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Best,<o:p class=""></o:p></div>
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Daniel<span class="Apple-converted-space"> </span><o:p class=""></o:p></div>
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<span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Wannier
mailing list</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<a href="mailto:Wannier@lists.quantum-espresso.org" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">Wannier@lists.quantum-espresso.org</a><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<a href="https://lists.quantum-espresso.org/mailman/listinfo/wannier" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">https://lists.quantum-espresso.org/mailman/listinfo/wannier</a></div>
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