<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>Il giorno 09/giu/2011, alle ore 03.44, Huiqun Zhou ha scritto:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Paolo,<br><br>Yes, I had used that option. My question is that which library we should <br>choose, the multi-thread<br>version, libmkl_intel_thread.a or the sequential version, <br>libmkl_sequential.a, of Intel MKL when<br>compiling mixed MPI+OpenMP version of qe? Or, in other words, do we need to <br>take advantage<br>of multi-threading functinality of Intel MKL when compiling MPI+OpenMP <br>version?<br></div></blockquote><div><br></div><div>That's a good question, maybe it has already been asked, so you might gather some information on the archives. I don't know if anyone has a clear answer to it. It looks to me that the threaded MKL are not so efficient (i.e. you will probably not gain much by running more than one thread on a multicore cpu). If you could do some testing and share with us it would be nice. This might also depend a lot on the hardware that you have at hand and on the MKL version (maybe things have been improved in the meanwhile), so please specify both. You could do this test even in serial mode (without MPI compilation), it should already give some answers.</div><div><br></div><div>If you compile MPI+OpenMP, it means that you are going to do large scale calculations (i.e., lots of atoms, lots of cpus,...). Then, remember that's very important to link against ScaLapack libraries. </div><div><br></div><div><br></div><div>Regards,</div><div><br></div><div>GS</div><div><br></div><blockquote type="cite"><div><br>Thanks!<br><br>zhou huiqun<br>@earth sciences, nanjing university, china<br><br><br>----- Original Message ----- <br>From: "Paolo Giannozzi" <<a href="mailto:giannozz@democritos.it">giannozz@democritos.it</a>><br>To: "PWSCF Forum" <<a href="mailto:pw_forum@pwscf.org">pw_forum@pwscf.org</a>><br>Sent: Wednesday, June 08, 2011 9:55 PM<br>Subject: Re: [Pw_forum] compile MPI+OpenMP version<br><br><br><blockquote type="cite"><br></blockquote><blockquote type="cite">On Jun 8, 2011, at 11:39 , Huiqun Zhou wrote:<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><blockquote type="cite">for MPI+OpenMP, should I use libmkl_intel_thread.a instead?<br></blockquote></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">you should use "./configure --enable-openmp [other options]"<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">P.<br></blockquote><blockquote type="cite">---<br></blockquote><blockquote type="cite">Paolo Giannozzi, Dept of Chemistry&Physics&Environment,<br></blockquote><blockquote type="cite">Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br></blockquote><blockquote type="cite">Phone +39-0432-558216, fax +39-0432-558222<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">_______________________________________________<br></blockquote><blockquote type="cite">Pw_forum mailing list<br></blockquote><blockquote type="cite"><a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br></blockquote><blockquote type="cite"><a href="http://www.democritos.it/mailman/listinfo/pw_forum">http://www.democritos.it/mailman/listinfo/pw_forum</a><br></blockquote><blockquote type="cite"><br></blockquote><br><br>_______________________________________________<br>Pw_forum mailing list<br><a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br>http://www.democritos.it/mailman/listinfo/pw_forum<br></div></blockquote></div><br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div><span class="Apple-style-span" style="color: rgb(126, 126, 126); font-size: 16px; font-style: italic; "><br class="Apple-interchange-newline">§ Gabriele Sclauzero, EPFL SB ITP CSEA</span></div><div><font class="Apple-style-span" color="#7E7E7E"><i> PH H2 462, Station 3, CH-1015 Lausanne</i></font></div></span>
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