<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body ><div><div></div><div>Hello Paolo,</div><div>Thank you very much.</div><div><br></div><div><div style="font-size:75%;color:#575757">Sent from Samsung Mobile</div></div></div><br><br><br>-------- Original message --------<br>From: Paolo Giannozzi <paolo.giannozzi@uniud.it> <br>Date: 17/01/2014 14:40 (GMT+00:00) <br>To: PWSCF Forum <pw_forum@pwscf.org> <br>Subject: Re: [Pw_forum] PARA_PREFIX AND PARA_IMAGE_POSTFIX <br> <br><br>On Fri, 2014-01-17 at 13:26 +0000, Elliot Menkah wrote:<br><br>> I'm working with a cluster with a total of 128 cores <br>> and I want to run a job(relax calculation) with pw.x using 64 cores.<br>> <br>> I'm a bit baffled with the number of processors to set for <br>> PARA_IMAGE_PREFIX<br><br>PARA_IMAGE_PREFIX is used by examples that run the phonon code<br>using the "image" parallelization. If all you need is to run<br>the self-consistent code, you do not need it.<br><br>P.<br><br>> since it should be a product of<br>> number of processors in PARA_PREFIX and the number of images in <br>> PARA_IMAGE_POSTFIX.<br>> <br>> When i set -np of PARA_PREFIX to be 64 what should the ideal -np be for <br>> PARA_POSTFIX?<br>> <br>> 64x64 = 4096<br>> <br>> the total cores are 128, so 4096 exceeds it.<br>> <br>> Any help or explanation on that is appreciated.<br>> <br>> Thank you.<br>> <br>> Regards,<br>> <br>> Elliot<br>> <br><br>-- <br> Paolo Giannozzi, Dept. Chemistry&Physics&Environment, <br> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br> Phone +39-0432-558216, fax +39-0432-558222 <br><br>_______________________________________________<br>Pw_forum mailing list<br>Pw_forum@pwscf.org<br>http://pwscf.org/mailman/listinfo/pw_forum<br></body>