<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>Il giorno 02/feb/2011, alle ore 03.54, <a href="mailto:ac.rain@inbox.com">ac.rain@inbox.com</a> ha scritto:</div><blockquote type="cite"><div><font class="Apple-style-span" color="#000000"><br></font>I am running it now in blocks of 4 cpus to match the number-combination requirement.<br>4 cores on the same system completes in 1h47m , 16 cores on the same system completes in 2h19m.<br><br>Is this not going to get faster on a single system until we add more memory to the system? or perhaps to drop the number of cpus specified in mpiMachinefile.txt so it spreads a fewer number of jobs over a greater number of systems? </div></blockquote><br><blockquote type="cite"><div>or is the bottleneck to do with the local hard drives not being fast enough?<br></div></blockquote><div><br></div>This should be easy to test, by changing the value in disk_io</div><div><br><blockquote type="cite"><div><br>I am not familiar with the maths equations/terminology mentioned in the document.<br></div></blockquote><div><br></div><div>Also your terminology is not familiar to us and is not easy to understand what you are saying... what is the "number-combination requirement"? And what does it mean "it spreads a fewer number of jobs over a greater number of systems"? Please make an effort to adopt more clear statements (reading some reviews or following a small tutorial on parallel/high-performance computing might help), otherwise we can only continue to guess what you mean.</div><div><br></div><div>In order to improve the speed up you should understand (at least broadly) the different levels of parallelization implemented in the code. Another important thing is to understand the timings at the end of the output. Try to compare those numbers for the two different runs.</div><div><br></div><div><br></div><div>GS</div><br><blockquote type="cite"><div><br>thanks,<br><br>nick<br><br><blockquote type="cite">-----Original Message-----<br></blockquote><blockquote type="cite">From: <a href="mailto:giannozz@democritos.it">giannozz@democritos.it</a><br></blockquote><blockquote type="cite">Sent: Mon, 31 Jan 2011 11:16:06 +0100<br></blockquote><blockquote type="cite">To: <a href="mailto:pw_forum@pwscf.org">pw_forum@pwscf.org</a><br></blockquote><blockquote type="cite">Subject: Re: [Pw_forum] QE and mpich2, Linux<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">in order to take advantage of parallelization, some understanding of<br></blockquote><blockquote type="cite">how parallelization works in QE is needed. The user guide and this<br></blockquote><blockquote type="cite">document:<br></blockquote><blockquote type="cite"><a href="http://www.fisica.uniud.it/~giannozz/QE-Tutorial/tutorial_para.pdf">http://www.fisica.uniud.it/~giannozz/QE-Tutorial/tutorial_para.pdf</a><br></blockquote><blockquote type="cite">contain some info. Throwing in more processors will not by itself do<br></blockquote><blockquote type="cite">the job.<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><br>____________________________________________________________<br>Send your photos by email in seconds...<br>TRY FREE IM TOOLPACK at <a href="http://www.imtoolpack.com/default.aspx?rc=if3">http://www.imtoolpack.com/default.aspx?rc=if3</a><br>Works in all emails, instant messengers, blogs, forums and social networks.<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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