[Pw_forum] On the run of GPU version of QE

[Alexander G. Kvashnin]

Dear Filippo,

I ran test job for vc-relax of NaCl crystal both on CPU only and GPU. I
found that wall time of the CPU job is (29 minutes) which less than time
given me by GPU job (49 minutes). I used the same command line for start as
I wrote in previous email. Could you please explain for what size of the
system or for what kind of jobs should I get an advantage with GPU rather
than CPU?

Thank you!

 *--*

*Sincerely yours,*
*Alexander G. Kvashnin *


*=====================================================PhD Student Moscow
Institute of Physics and Technology          http://mipt.ru/
<http://s.wisestamp.com/links?url=http%3A%2F%2Fmipt.ru%2F&sn=>*
*141700, Institutsky lane 9, Dolgoprudny, Moscow Region, Russia*





*Junior research scientistTechnological Institute for Superhard and Novel
Carbon Materials                                http://www.tisnum.ru/
<http://s.wisestamp.com/links?url=http%3A%2F%2Fwww.tisnum.ru%2F&sn=>
<http://s.wisestamp.com/links?url=http%3A%2F%2Fwww.ntcstm.troitsk.ru%2F&sn=>142190,
Central'naya St. 7a, Troitsk, Moscow Region,
Russia=====================================================*



On 26 March 2014 19:13, Filippo Spiga <spiga.filippo at gmail.com> wrote:

>
> On Mar 26, 2014, at 12:33 AM, Alexander G. Kvashnin <agkvashnin at gmail.com>
> wrote:
> > mpirun -np 2 /qe-dir/bin/pw-gpu.x -in input > output
> >
> > And it will start with 2 MPI process and get 2 GPUs on my host. Is it
> correct?
>
> Yes. But if 2 MPI processes are enough to run the calculation I suggest to
> run the code in serial. The GPU acceleration will be probably faster.
>
> F
>
> --
> Mr. Filippo SPIGA, M.Sc.
> http://www.linkedin.com/in/filippospiga ~ skype: filippo.spiga
>
> «Nobody will drive us out of Cantor's paradise.» ~ David Hilbert
>
> *****
> Disclaimer: "Please note this message and any attachments are CONFIDENTIAL
> and may be privileged or otherwise protected from disclosure. The contents
> are not to be disclosed to anyone other than the addressee. Unauthorized
> recipients are requested to preserve this confidentiality and to advise the
> sender immediately of any error in transmission."
>
>
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20140328/e41e7d8e/attachment.html>